This is make.info, produced by makeinfo version 6.6 from make.texi. This file documents the GNU 'make' utility, which determines automatically which pieces of a large program need to be recompiled, and issues the commands to recompile them. This is Edition 0.75, last updated 19 January 2020, of 'The GNU Make Manual', for GNU 'make' version 4.3. Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 Free Software Foundation, Inc. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with the Front-Cover Texts being "A GNU Manual," and with the Back-Cover Texts as in (a) below. A copy of the license is included in the section entitled "GNU Free Documentation License." (a) The FSF's Back-Cover Text is: "You have the freedom to copy and modify this GNU manual. Buying copies from the FSF supports it in developing GNU and promoting software freedom." INFO-DIR-SECTION Software development START-INFO-DIR-ENTRY * Make: (make). Remake files automatically. END-INFO-DIR-ENTRY  File: make.info, Node: Testing, Next: Options Summary, Prev: Overriding, Up: Running 9.6 Testing the Compilation of a Program ======================================== Normally, when an error happens in executing a shell command, 'make' gives up immediately, returning a nonzero status. No further recipes are executed for any target. The error implies that the goal cannot be correctly remade, and 'make' reports this as soon as it knows. When you are compiling a program that you have just changed, this is not what you want. Instead, you would rather that 'make' try compiling every file that can be tried, to show you as many compilation errors as possible. On these occasions, you should use the '-k' or '--keep-going' flag. This tells 'make' to continue to consider the other prerequisites of the pending targets, remaking them if necessary, before it gives up and returns nonzero status. For example, after an error in compiling one object file, 'make -k' will continue compiling other object files even though it already knows that linking them will be impossible. In addition to continuing after failed shell commands, 'make -k' will continue as much as possible after discovering that it does not know how to make a target or prerequisite file. This will always cause an error message, but without '-k', it is a fatal error (*note Summary of Options: Options Summary.). The usual behavior of 'make' assumes that your purpose is to get the goals up to date; once 'make' learns that this is impossible, it might as well report the failure immediately. The '-k' flag says that the real purpose is to test as much as possible of the changes made in the program, perhaps to find several independent problems so that you can correct them all before the next attempt to compile. This is why Emacs' 'M-x compile' command passes the '-k' flag by default.  File: make.info, Node: Options Summary, Prev: Testing, Up: Running 9.7 Summary of Options ====================== Here is a table of all the options 'make' understands: '-b' '-m' These options are ignored for compatibility with other versions of 'make'. '-B' '--always-make' Consider all targets out-of-date. GNU 'make' proceeds to consider targets and their prerequisites using the normal algorithms; however, all targets so considered are always remade regardless of the status of their prerequisites. To avoid infinite recursion, if 'MAKE_RESTARTS' (*note Other Special Variables: Special Variables.) is set to a number greater than 0 this option is disabled when considering whether to remake makefiles (*note How Makefiles Are Remade: Remaking Makefiles.). '-C DIR' '--directory=DIR' Change to directory DIR before reading the makefiles. If multiple '-C' options are specified, each is interpreted relative to the previous one: '-C / -C etc' is equivalent to '-C /etc'. This is typically used with recursive invocations of 'make' (*note Recursive Use of 'make': Recursion.). '-d' Print debugging information in addition to normal processing. The debugging information says which files are being considered for remaking, which file-times are being compared and with what results, which files actually need to be remade, which implicit rules are considered and which are applied--everything interesting about how 'make' decides what to do. The '-d' option is equivalent to '--debug=a' (see below). '--debug[=OPTIONS]' Print debugging information in addition to normal processing. Various levels and types of output can be chosen. With no arguments, print the "basic" level of debugging. Possible arguments are below; only the first character is considered, and values must be comma- or space-separated. 'a (all)' All types of debugging output are enabled. This is equivalent to using '-d'. 'b (basic)' Basic debugging prints each target that was found to be out-of-date, and whether the build was successful or not. 'v (verbose)' A level above 'basic'; includes messages about which makefiles were parsed, prerequisites that did not need to be rebuilt, etc. This option also enables 'basic' messages. 'i (implicit)' Prints messages describing the implicit rule searches for each target. This option also enables 'basic' messages. 'j (jobs)' Prints messages giving details on the invocation of specific sub-commands. 'm (makefile)' By default, the above messages are not enabled while trying to remake the makefiles. This option enables messages while rebuilding makefiles, too. Note that the 'all' option does enable this option. This option also enables 'basic' messages. 'n (none)' Disable all debugging currently enabled. If additional debugging flags are encountered after this they will still take effect. '-e' '--environment-overrides' Give variables taken from the environment precedence over variables from makefiles. *Note Variables from the Environment: Environment. '-E STRING' '--eval=STRING' Evaluate STRING as makefile syntax. This is a command-line version of the 'eval' function (*note Eval Function::). The evaluation is performed after the default rules and variables have been defined, but before any makefiles are read. '-f FILE' '--file=FILE' '--makefile=FILE' Read the file named FILE as a makefile. *Note Writing Makefiles: Makefiles. '-h' '--help' Remind you of the options that 'make' understands and then exit. '-i' '--ignore-errors' Ignore all errors in recipes executed to remake files. *Note Errors in Recipes: Errors. '-I DIR' '--include-dir=DIR' Specifies a directory DIR to search for included makefiles. *Note Including Other Makefiles: Include. If several '-I' options are used to specify several directories, the directories are searched in the order specified. '-j [JOBS]' '--jobs[=JOBS]' Specifies the number of recipes (jobs) to run simultaneously. With no argument, 'make' runs as many recipes simultaneously as possible. If there is more than one '-j' option, the last one is effective. *Note Parallel Execution: Parallel, for more information on how recipes are run. Note that this option is ignored on MS-DOS. '-k' '--keep-going' Continue as much as possible after an error. While the target that failed, and those that depend on it, cannot be remade, the other prerequisites of these targets can be processed all the same. *Note Testing the Compilation of a Program: Testing. '-l [LOAD]' '--load-average[=LOAD]' '--max-load[=LOAD]' Specifies that no new recipes should be started if there are other recipes running and the load average is at least LOAD (a floating-point number). With no argument, removes a previous load limit. *Note Parallel Execution: Parallel. '-L' '--check-symlink-times' On systems that support symbolic links, this option causes 'make' to consider the timestamps on any symbolic links in addition to the timestamp on the file referenced by those links. When this option is provided, the most recent timestamp among the file and the symbolic links is taken as the modification time for this target file. '-n' '--just-print' '--dry-run' '--recon' Print the recipe that would be executed, but do not execute it (except in certain circumstances). *Note Instead of Executing Recipes: Instead of Execution. '-o FILE' '--old-file=FILE' '--assume-old=FILE' Do not remake the file FILE even if it is older than its prerequisites, and do not remake anything on account of changes in FILE. Essentially the file is treated as very old and its rules are ignored. *Note Avoiding Recompilation of Some Files: Avoiding Compilation. '-O[TYPE]' '--output-sync[=TYPE]' Ensure that the complete output from each recipe is printed in one uninterrupted sequence. This option is only useful when using the '--jobs' option to run multiple recipes simultaneously (*note Parallel Execution: Parallel.) Without this option output will be displayed as it is generated by the recipes. With no type or the type 'target', output from the entire recipe of each target is grouped together. With the type 'line', output from each line in the recipe is grouped together. With the type 'recurse', the output from an entire recursive make is grouped together. With the type 'none', no output synchronization is performed. *Note Output During Parallel Execution: Parallel Output. '-p' '--print-data-base' Print the data base (rules and variable values) that results from reading the makefiles; then execute as usual or as otherwise specified. This also prints the version information given by the '-v' switch (see below). To print the data base without trying to remake any files, use 'make -qp'. To print the data base of predefined rules and variables, use 'make -p -f /dev/null'. The data base output contains file name and line number information for recipe and variable definitions, so it can be a useful debugging tool in complex environments. '-q' '--question' "Question mode". Do not run any recipes, or print anything; just return an exit status that is zero if the specified targets are already up to date, one if any remaking is required, or two if an error is encountered. *Note Instead of Executing Recipes: Instead of Execution. '-r' '--no-builtin-rules' Eliminate use of the built-in implicit rules (*note Using Implicit Rules: Implicit Rules.). You can still define your own by writing pattern rules (*note Defining and Redefining Pattern Rules: Pattern Rules.). The '-r' option also clears out the default list of suffixes for suffix rules (*note Old-Fashioned Suffix Rules: Suffix Rules.). But you can still define your own suffixes with a rule for '.SUFFIXES', and then define your own suffix rules. Note that only _rules_ are affected by the '-r' option; default variables remain in effect (*note Variables Used by Implicit Rules: Implicit Variables.); see the '-R' option below. '-R' '--no-builtin-variables' Eliminate use of the built-in rule-specific variables (*note Variables Used by Implicit Rules: Implicit Variables.). You can still define your own, of course. The '-R' option also automatically enables the '-r' option (see above), since it doesn't make sense to have implicit rules without any definitions for the variables that they use. '-s' '--silent' '--quiet' Silent operation; do not print the recipes as they are executed. *Note Recipe Echoing: Echoing. '-S' '--no-keep-going' '--stop' Cancel the effect of the '-k' option. This is never necessary except in a recursive 'make' where '-k' might be inherited from the top-level 'make' via 'MAKEFLAGS' (*note Recursive Use of 'make': Recursion.) or if you set '-k' in 'MAKEFLAGS' in your environment. '-t' '--touch' Touch files (mark them up to date without really changing them) instead of running their recipes. This is used to pretend that the recipes were done, in order to fool future invocations of 'make'. *Note Instead of Executing Recipes: Instead of Execution. '--trace' Show tracing information for 'make' execution. Prints the entire recipe to be executed, even for recipes that are normally silent (due to '.SILENT' or '@'). Also prints the makefile name and line number where the recipe was defined, and information on why the target is being rebuilt. '-v' '--version' Print the version of the 'make' program plus a copyright, a list of authors, and a notice that there is no warranty; then exit. '-w' '--print-directory' Print a message containing the working directory both before and after executing the makefile. This may be useful for tracking down errors from complicated nests of recursive 'make' commands. *Note Recursive Use of 'make': Recursion. (In practice, you rarely need to specify this option since 'make' does it for you; see *note The '--print-directory' Option: -w Option.) '--no-print-directory' Disable printing of the working directory under '-w'. This option is useful when '-w' is turned on automatically, but you do not want to see the extra messages. *Note The '--print-directory' Option: -w Option. '-W FILE' '--what-if=FILE' '--new-file=FILE' '--assume-new=FILE' Pretend that the target FILE has just been modified. When used with the '-n' flag, this shows you what would happen if you were to modify that file. Without '-n', it is almost the same as running a 'touch' command on the given file before running 'make', except that the modification time is changed only in the imagination of 'make'. *Note Instead of Executing Recipes: Instead of Execution. '--warn-undefined-variables' Issue a warning message whenever 'make' sees a reference to an undefined variable. This can be helpful when you are trying to debug makefiles which use variables in complex ways.  File: make.info, Node: Implicit Rules, Next: Archives, Prev: Running, Up: Top 10 Using Implicit Rules *********************** Certain standard ways of remaking target files are used very often. For example, one customary way to make an object file is from a C source file using the C compiler, 'cc'. "Implicit rules" tell 'make' how to use customary techniques so that you do not have to specify them in detail when you want to use them. For example, there is an implicit rule for C compilation. File names determine which implicit rules are run. For example, C compilation typically takes a '.c' file and makes a '.o' file. So 'make' applies the implicit rule for C compilation when it sees this combination of file name endings. A chain of implicit rules can apply in sequence; for example, 'make' will remake a '.o' file from a '.y' file by way of a '.c' file. The built-in implicit rules use several variables in their recipes so that, by changing the values of the variables, you can change the way the implicit rule works. For example, the variable 'CFLAGS' controls the flags given to the C compiler by the implicit rule for C compilation. You can define your own implicit rules by writing "pattern rules". "Suffix rules" are a more limited way to define implicit rules. Pattern rules are more general and clearer, but suffix rules are retained for compatibility. * Menu: * Using Implicit:: How to use an existing implicit rule to get the recipes for updating a file. * Catalogue of Rules:: A list of built-in rules. * Implicit Variables:: How to change what predefined rules do. * Chained Rules:: How to use a chain of implicit rules. * Pattern Rules:: How to define new implicit rules. * Last Resort:: How to define a recipe for rules which cannot find any. * Suffix Rules:: The old-fashioned style of implicit rule. * Implicit Rule Search:: The precise algorithm for applying implicit rules.  File: make.info, Node: Using Implicit, Next: Catalogue of Rules, Prev: Implicit Rules, Up: Implicit Rules 10.1 Using Implicit Rules ========================= To allow 'make' to find a customary method for updating a target file, all you have to do is refrain from specifying recipes yourself. Either write a rule with no recipe, or don't write a rule at all. Then 'make' will figure out which implicit rule to use based on which kind of source file exists or can be made. For example, suppose the makefile looks like this: foo : foo.o bar.o cc -o foo foo.o bar.o $(CFLAGS) $(LDFLAGS) Because you mention 'foo.o' but do not give a rule for it, 'make' will automatically look for an implicit rule that tells how to update it. This happens whether or not the file 'foo.o' currently exists. If an implicit rule is found, it can supply both a recipe and one or more prerequisites (the source files). You would want to write a rule for 'foo.o' with no recipe if you need to specify additional prerequisites, such as header files, that the implicit rule cannot supply. Each implicit rule has a target pattern and prerequisite patterns. There may be many implicit rules with the same target pattern. For example, numerous rules make '.o' files: one, from a '.c' file with the C compiler; another, from a '.p' file with the Pascal compiler; and so on. The rule that actually applies is the one whose prerequisites exist or can be made. So, if you have a file 'foo.c', 'make' will run the C compiler; otherwise, if you have a file 'foo.p', 'make' will run the Pascal compiler; and so on. Of course, when you write the makefile, you know which implicit rule you want 'make' to use, and you know it will choose that one because you know which possible prerequisite files are supposed to exist. *Note Catalogue of Built-In Rules: Catalogue of Rules, for a catalogue of all the predefined implicit rules. Above, we said an implicit rule applies if the required prerequisites "exist or can be made". A file "can be made" if it is mentioned explicitly in the makefile as a target or a prerequisite, or if an implicit rule can be recursively found for how to make it. When an implicit prerequisite is the result of another implicit rule, we say that "chaining" is occurring. *Note Chains of Implicit Rules: Chained Rules. In general, 'make' searches for an implicit rule for each target, and for each double-colon rule, that has no recipe. A file that is mentioned only as a prerequisite is considered a target whose rule specifies nothing, so implicit rule search happens for it. *Note Implicit Rule Search Algorithm: Implicit Rule Search, for the details of how the search is done. Note that explicit prerequisites do not influence implicit rule search. For example, consider this explicit rule: foo.o: foo.p The prerequisite on 'foo.p' does not necessarily mean that 'make' will remake 'foo.o' according to the implicit rule to make an object file, a '.o' file, from a Pascal source file, a '.p' file. For example, if 'foo.c' also exists, the implicit rule to make an object file from a C source file is used instead, because it appears before the Pascal rule in the list of predefined implicit rules (*note Catalogue of Built-In Rules: Catalogue of Rules.). If you do not want an implicit rule to be used for a target that has no recipe, you can give that target an empty recipe by writing a semicolon (*note Defining Empty Recipes: Empty Recipes.).  File: make.info, Node: Catalogue of Rules, Next: Implicit Variables, Prev: Using Implicit, Up: Implicit Rules 10.2 Catalogue of Built-In Rules ================================ Here is a catalogue of predefined implicit rules which are always available unless the makefile explicitly overrides or cancels them. *Note Canceling Implicit Rules: Canceling Rules, for information on canceling or overriding an implicit rule. The '-r' or '--no-builtin-rules' option cancels all predefined rules. This manual only documents the default rules available on POSIX-based operating systems. Other operating systems, such as VMS, Windows, OS/2, etc. may have different sets of default rules. To see the full list of default rules and variables available in your version of GNU 'make', run 'make -p' in a directory with no makefile. Not all of these rules will always be defined, even when the '-r' option is not given. Many of the predefined implicit rules are implemented in 'make' as suffix rules, so which ones will be defined depends on the "suffix list" (the list of prerequisites of the special target '.SUFFIXES'). The default suffix list is: '.out', '.a', '.ln', '.o', '.c', '.cc', '.C', '.cpp', '.p', '.f', '.F', '.m', '.r', '.y', '.l', '.ym', '.lm', '.s', '.S', '.mod', '.sym', '.def', '.h', '.info', '.dvi', '.tex', '.texinfo', '.texi', '.txinfo', '.w', '.ch' '.web', '.sh', '.elc', '.el'. All of the implicit rules described below whose prerequisites have one of these suffixes are actually suffix rules. If you modify the suffix list, the only predefined suffix rules in effect will be those named by one or two of the suffixes that are on the list you specify; rules whose suffixes fail to be on the list are disabled. *Note Old-Fashioned Suffix Rules: Suffix Rules, for full details on suffix rules. Compiling C programs 'N.o' is made automatically from 'N.c' with a recipe of the form '$(CC) $(CPPFLAGS) $(CFLAGS) -c'. Compiling C++ programs 'N.o' is made automatically from 'N.cc', 'N.cpp', or 'N.C' with a recipe of the form '$(CXX) $(CPPFLAGS) $(CXXFLAGS) -c'. We encourage you to use the suffix '.cc' for C++ source files instead of '.C'. Compiling Pascal programs 'N.o' is made automatically from 'N.p' with the recipe '$(PC) $(PFLAGS) -c'. Compiling Fortran and Ratfor programs 'N.o' is made automatically from 'N.r', 'N.F' or 'N.f' by running the Fortran compiler. The precise recipe used is as follows: '.f' '$(FC) $(FFLAGS) -c'. '.F' '$(FC) $(FFLAGS) $(CPPFLAGS) -c'. '.r' '$(FC) $(FFLAGS) $(RFLAGS) -c'. Preprocessing Fortran and Ratfor programs 'N.f' is made automatically from 'N.r' or 'N.F'. This rule runs just the preprocessor to convert a Ratfor or preprocessable Fortran program into a strict Fortran program. The precise recipe used is as follows: '.F' '$(FC) $(CPPFLAGS) $(FFLAGS) -F'. '.r' '$(FC) $(FFLAGS) $(RFLAGS) -F'. Compiling Modula-2 programs 'N.sym' is made from 'N.def' with a recipe of the form '$(M2C) $(M2FLAGS) $(DEFFLAGS)'. 'N.o' is made from 'N.mod'; the form is: '$(M2C) $(M2FLAGS) $(MODFLAGS)'. Assembling and preprocessing assembler programs 'N.o' is made automatically from 'N.s' by running the assembler, 'as'. The precise recipe is '$(AS) $(ASFLAGS)'. 'N.s' is made automatically from 'N.S' by running the C preprocessor, 'cpp'. The precise recipe is '$(CPP) $(CPPFLAGS)'. Linking a single object file 'N' is made automatically from 'N.o' by running the linker (usually called 'ld') via the C compiler. The precise recipe used is '$(CC) $(LDFLAGS) N.o $(LOADLIBES) $(LDLIBS)'. This rule does the right thing for a simple program with only one source file. It will also do the right thing if there are multiple object files (presumably coming from various other source files), one of which has a name matching that of the executable file. Thus, x: y.o z.o when 'x.c', 'y.c' and 'z.c' all exist will execute: cc -c x.c -o x.o cc -c y.c -o y.o cc -c z.c -o z.o cc x.o y.o z.o -o x rm -f x.o rm -f y.o rm -f z.o In more complicated cases, such as when there is no object file whose name derives from the executable file name, you must write an explicit recipe for linking. Each kind of file automatically made into '.o' object files will be automatically linked by using the compiler ('$(CC)', '$(FC)' or '$(PC)'; the C compiler '$(CC)' is used to assemble '.s' files) without the '-c' option. This could be done by using the '.o' object files as intermediates, but it is faster to do the compiling and linking in one step, so that's how it's done. Yacc for C programs 'N.c' is made automatically from 'N.y' by running Yacc with the recipe '$(YACC) $(YFLAGS)'. Lex for C programs 'N.c' is made automatically from 'N.l' by running Lex. The actual recipe is '$(LEX) $(LFLAGS)'. Lex for Ratfor programs 'N.r' is made automatically from 'N.l' by running Lex. The actual recipe is '$(LEX) $(LFLAGS)'. The convention of using the same suffix '.l' for all Lex files regardless of whether they produce C code or Ratfor code makes it impossible for 'make' to determine automatically which of the two languages you are using in any particular case. If 'make' is called upon to remake an object file from a '.l' file, it must guess which compiler to use. It will guess the C compiler, because that is more common. If you are using Ratfor, make sure 'make' knows this by mentioning 'N.r' in the makefile. Or, if you are using Ratfor exclusively, with no C files, remove '.c' from the list of implicit rule suffixes with: .SUFFIXES: .SUFFIXES: .o .r .f .l ... Making Lint Libraries from C, Yacc, or Lex programs 'N.ln' is made from 'N.c' by running 'lint'. The precise recipe is '$(LINT) $(LINTFLAGS) $(CPPFLAGS) -i'. The same recipe is used on the C code produced from 'N.y' or 'N.l'. TeX and Web 'N.dvi' is made from 'N.tex' with the recipe '$(TEX)'. 'N.tex' is made from 'N.web' with '$(WEAVE)', or from 'N.w' (and from 'N.ch' if it exists or can be made) with '$(CWEAVE)'. 'N.p' is made from 'N.web' with '$(TANGLE)' and 'N.c' is made from 'N.w' (and from 'N.ch' if it exists or can be made) with '$(CTANGLE)'. Texinfo and Info 'N.dvi' is made from 'N.texinfo', 'N.texi', or 'N.txinfo', with the recipe '$(TEXI2DVI) $(TEXI2DVI_FLAGS)'. 'N.info' is made from 'N.texinfo', 'N.texi', or 'N.txinfo', with the recipe '$(MAKEINFO) $(MAKEINFO_FLAGS)'. RCS Any file 'N' is extracted if necessary from an RCS file named either 'N,v' or 'RCS/N,v'. The precise recipe used is '$(CO) $(COFLAGS)'. 'N' will not be extracted from RCS if it already exists, even if the RCS file is newer. The rules for RCS are terminal (*note Match-Anything Pattern Rules: Match-Anything Rules.), so RCS files cannot be generated from another source; they must actually exist. SCCS Any file 'N' is extracted if necessary from an SCCS file named either 's.N' or 'SCCS/s.N'. The precise recipe used is '$(GET) $(GFLAGS)'. The rules for SCCS are terminal (*note Match-Anything Pattern Rules: Match-Anything Rules.), so SCCS files cannot be generated from another source; they must actually exist. For the benefit of SCCS, a file 'N' is copied from 'N.sh' and made executable (by everyone). This is for shell scripts that are checked into SCCS. Since RCS preserves the execution permission of a file, you do not need to use this feature with RCS. We recommend that you avoid using of SCCS. RCS is widely held to be superior, and is also free. By choosing free software in place of comparable (or inferior) proprietary software, you support the free software movement. Usually, you want to change only the variables listed in the table above, which are documented in the following section. However, the recipes in built-in implicit rules actually use variables such as 'COMPILE.c', 'LINK.p', and 'PREPROCESS.S', whose values contain the recipes listed above. 'make' follows the convention that the rule to compile a '.X' source file uses the variable 'COMPILE.X'. Similarly, the rule to produce an executable from a '.X' file uses 'LINK.X'; and the rule to preprocess a '.X' file uses 'PREPROCESS.X'. Every rule that produces an object file uses the variable 'OUTPUT_OPTION'. 'make' defines this variable either to contain '-o $@', or to be empty, depending on a compile-time option. You need the '-o' option to ensure that the output goes into the right file when the source file is in a different directory, as when using 'VPATH' (*note Directory Search::). However, compilers on some systems do not accept a '-o' switch for object files. If you use such a system, and use 'VPATH', some compilations will put their output in the wrong place. A possible workaround for this problem is to give 'OUTPUT_OPTION' the value '; mv $*.o $@'.  File: make.info, Node: Implicit Variables, Next: Chained Rules, Prev: Catalogue of Rules, Up: Implicit Rules 10.3 Variables Used by Implicit Rules ===================================== The recipes in built-in implicit rules make liberal use of certain predefined variables. You can alter the values of these variables in the makefile, with arguments to 'make', or in the environment to alter how the implicit rules work without redefining the rules themselves. You can cancel all variables used by implicit rules with the '-R' or '--no-builtin-variables' option. For example, the recipe used to compile a C source file actually says '$(CC) -c $(CFLAGS) $(CPPFLAGS)'. The default values of the variables used are 'cc' and nothing, resulting in the command 'cc -c'. By redefining 'CC' to 'ncc', you could cause 'ncc' to be used for all C compilations performed by the implicit rule. By redefining 'CFLAGS' to be '-g', you could pass the '-g' option to each compilation. _All_ implicit rules that do C compilation use '$(CC)' to get the program name for the compiler and _all_ include '$(CFLAGS)' among the arguments given to the compiler. The variables used in implicit rules fall into two classes: those that are names of programs (like 'CC') and those that contain arguments for the programs (like 'CFLAGS'). (The "name of a program" may also contain some command arguments, but it must start with an actual executable program name.) If a variable value contains more than one argument, separate them with spaces. The following tables describe of some of the more commonly-used predefined variables. This list is not exhaustive, and the default values shown here may not be what 'make' selects for your environment. To see the complete list of predefined variables for your instance of GNU 'make' you can run 'make -p' in a directory with no makefiles. Here is a table of some of the more common variables used as names of programs in built-in rules: 'AR' Archive-maintaining program; default 'ar'. 'AS' Program for compiling assembly files; default 'as'. 'CC' Program for compiling C programs; default 'cc'. 'CXX' Program for compiling C++ programs; default 'g++'. 'CPP' Program for running the C preprocessor, with results to standard output; default '$(CC) -E'. 'FC' Program for compiling or preprocessing Fortran and Ratfor programs; default 'f77'. 'M2C' Program to use to compile Modula-2 source code; default 'm2c'. 'PC' Program for compiling Pascal programs; default 'pc'. 'CO' Program for extracting a file from RCS; default 'co'. 'GET' Program for extracting a file from SCCS; default 'get'. 'LEX' Program to use to turn Lex grammars into source code; default 'lex'. 'YACC' Program to use to turn Yacc grammars into source code; default 'yacc'. 'LINT' Program to use to run lint on source code; default 'lint'. 'MAKEINFO' Program to convert a Texinfo source file into an Info file; default 'makeinfo'. 'TEX' Program to make TeX DVI files from TeX source; default 'tex'. 'TEXI2DVI' Program to make TeX DVI files from Texinfo source; default 'texi2dvi'. 'WEAVE' Program to translate Web into TeX; default 'weave'. 'CWEAVE' Program to translate C Web into TeX; default 'cweave'. 'TANGLE' Program to translate Web into Pascal; default 'tangle'. 'CTANGLE' Program to translate C Web into C; default 'ctangle'. 'RM' Command to remove a file; default 'rm -f'. Here is a table of variables whose values are additional arguments for the programs above. The default values for all of these is the empty string, unless otherwise noted. 'ARFLAGS' Flags to give the archive-maintaining program; default 'rv'. 'ASFLAGS' Extra flags to give to the assembler (when explicitly invoked on a '.s' or '.S' file). 'CFLAGS' Extra flags to give to the C compiler. 'CXXFLAGS' Extra flags to give to the C++ compiler. 'COFLAGS' Extra flags to give to the RCS 'co' program. 'CPPFLAGS' Extra flags to give to the C preprocessor and programs that use it (the C and Fortran compilers). 'FFLAGS' Extra flags to give to the Fortran compiler. 'GFLAGS' Extra flags to give to the SCCS 'get' program. 'LDFLAGS' Extra flags to give to compilers when they are supposed to invoke the linker, 'ld', such as '-L'. Libraries ('-lfoo') should be added to the 'LDLIBS' variable instead. 'LDLIBS' Library flags or names given to compilers when they are supposed to invoke the linker, 'ld'. 'LOADLIBES' is a deprecated (but still supported) alternative to 'LDLIBS'. Non-library linker flags, such as '-L', should go in the 'LDFLAGS' variable. 'LFLAGS' Extra flags to give to Lex. 'YFLAGS' Extra flags to give to Yacc. 'PFLAGS' Extra flags to give to the Pascal compiler. 'RFLAGS' Extra flags to give to the Fortran compiler for Ratfor programs. 'LINTFLAGS' Extra flags to give to lint.  File: make.info, Node: Chained Rules, Next: Pattern Rules, Prev: Implicit Variables, Up: Implicit Rules 10.4 Chains of Implicit Rules ============================= Sometimes a file can be made by a sequence of implicit rules. For example, a file 'N.o' could be made from 'N.y' by running first Yacc and then 'cc'. Such a sequence is called a "chain". If the file 'N.c' exists, or is mentioned in the makefile, no special searching is required: 'make' finds that the object file can be made by C compilation from 'N.c'; later on, when considering how to make 'N.c', the rule for running Yacc is used. Ultimately both 'N.c' and 'N.o' are updated. However, even if 'N.c' does not exist and is not mentioned, 'make' knows how to envision it as the missing link between 'N.o' and 'N.y'! In this case, 'N.c' is called an "intermediate file". Once 'make' has decided to use the intermediate file, it is entered in the data base as if it had been mentioned in the makefile, along with the implicit rule that says how to create it. Intermediate files are remade using their rules just like all other files. But intermediate files are treated differently in two ways. The first difference is what happens if the intermediate file does not exist. If an ordinary file B does not exist, and 'make' considers a target that depends on B, it invariably creates B and then updates the target from B. But if B is an intermediate file, then 'make' can leave well enough alone. It won't bother updating B, or the ultimate target, unless some prerequisite of B is newer than that target or there is some other reason to update that target. The second difference is that if 'make' _does_ create B in order to update something else, it deletes B later on after it is no longer needed. Therefore, an intermediate file which did not exist before 'make' also does not exist after 'make'. 'make' reports the deletion to you by printing a 'rm -f' command showing which file it is deleting. Ordinarily, a file cannot be intermediate if it is mentioned in the makefile as a target or prerequisite. However, you can explicitly mark a file as intermediate by listing it as a prerequisite of the special target '.INTERMEDIATE'. This takes effect even if the file is mentioned explicitly in some other way. You can prevent automatic deletion of an intermediate file by marking it as a "secondary" file. To do this, list it as a prerequisite of the special target '.SECONDARY'. When a file is secondary, 'make' will not create the file merely because it does not already exist, but 'make' does not automatically delete the file. Marking a file as secondary also marks it as intermediate. You can list the target pattern of an implicit rule (such as '%.o') as a prerequisite of the special target '.PRECIOUS' to preserve intermediate files made by implicit rules whose target patterns match that file's name; see *note Interrupts::. A chain can involve more than two implicit rules. For example, it is possible to make a file 'foo' from 'RCS/foo.y,v' by running RCS, Yacc and 'cc'. Then both 'foo.y' and 'foo.c' are intermediate files that are deleted at the end. No single implicit rule can appear more than once in a chain. This means that 'make' will not even consider such a ridiculous thing as making 'foo' from 'foo.o.o' by running the linker twice. This constraint has the added benefit of preventing any infinite loop in the search for an implicit rule chain. There are some special implicit rules to optimize certain cases that would otherwise be handled by rule chains. For example, making 'foo' from 'foo.c' could be handled by compiling and linking with separate chained rules, using 'foo.o' as an intermediate file. But what actually happens is that a special rule for this case does the compilation and linking with a single 'cc' command. The optimized rule is used in preference to the step-by-step chain because it comes earlier in the ordering of rules. Finally, for performance reasons 'make' will not consider non-terminal match-anything rules (i.e., '%:') when searching for a rule to build a prerequisite of an implicit rule (*note Match-Anything Rules::).  File: make.info, Node: Pattern Rules, Next: Last Resort, Prev: Chained Rules, Up: Implicit Rules 10.5 Defining and Redefining Pattern Rules ========================================== You define an implicit rule by writing a "pattern rule". A pattern rule looks like an ordinary rule, except that its target contains the character '%' (exactly one of them). The target is considered a pattern for matching file names; the '%' can match any nonempty substring, while other characters match only themselves. The prerequisites likewise use '%' to show how their names relate to the target name. Thus, a pattern rule '%.o : %.c' says how to make any file 'STEM.o' from another file 'STEM.c'. Note that expansion using '%' in pattern rules occurs *after* any variable or function expansions, which take place when the makefile is read. *Note How to Use Variables: Using Variables, and *note Functions for Transforming Text: Functions. * Menu: * Pattern Intro:: An introduction to pattern rules. * Pattern Examples:: Examples of pattern rules. * Automatic Variables:: How to use automatic variables in the recipe of implicit rules. * Pattern Match:: How patterns match. * Match-Anything Rules:: Precautions you should take prior to defining rules that can match any target file whatever. * Canceling Rules:: How to override or cancel built-in rules.  File: make.info, Node: Pattern Intro, Next: Pattern Examples, Prev: Pattern Rules, Up: Pattern Rules 10.5.1 Introduction to Pattern Rules ------------------------------------ A pattern rule contains the character '%' (exactly one of them) in the target; otherwise, it looks exactly like an ordinary rule. The target is a pattern for matching file names; the '%' matches any nonempty substring, while other characters match only themselves. For example, '%.c' as a pattern matches any file name that ends in '.c'. 's.%.c' as a pattern matches any file name that starts with 's.', ends in '.c' and is at least five characters long. (There must be at least one character to match the '%'.) The substring that the '%' matches is called the "stem". '%' in a prerequisite of a pattern rule stands for the same stem that was matched by the '%' in the target. In order for the pattern rule to apply, its target pattern must match the file name under consideration and all of its prerequisites (after pattern substitution) must name files that exist or can be made. These files become prerequisites of the target. Thus, a rule of the form %.o : %.c ; RECIPE... specifies how to make a file 'N.o', with another file 'N.c' as its prerequisite, provided that 'N.c' exists or can be made. There may also be prerequisites that do not use '%'; such a prerequisite attaches to every file made by this pattern rule. These unvarying prerequisites are useful occasionally. A pattern rule need not have any prerequisites that contain '%', or in fact any prerequisites at all. Such a rule is effectively a general wildcard. It provides a way to make any file that matches the target pattern. *Note Last Resort::. More than one pattern rule may match a target. In this case 'make' will choose the "best fit" rule. *Note How Patterns Match: Pattern Match. Pattern rules may have more than one target; however, every target must contain a '%' character. Pattern rules are always treated as grouped targets (*note Multiple Targets in a Rule: Multiple Targets.) regardless of whether they use the ':' or '&:' separator.  File: make.info, Node: Pattern Examples, Next: Automatic Variables, Prev: Pattern Intro, Up: Pattern Rules 10.5.2 Pattern Rule Examples ---------------------------- Here are some examples of pattern rules actually predefined in 'make'. First, the rule that compiles '.c' files into '.o' files: %.o : %.c $(CC) -c $(CFLAGS) $(CPPFLAGS) $< -o $@ defines a rule that can make any file 'X.o' from 'X.c'. The recipe uses the automatic variables '$@' and '$<' to substitute the names of the target file and the source file in each case where the rule applies (*note Automatic Variables::). Here is a second built-in rule: % :: RCS/%,v $(CO) $(COFLAGS) $< defines a rule that can make any file 'X' whatsoever from a corresponding file 'X,v' in the sub-directory 'RCS'. Since the target is '%', this rule will apply to any file whatever, provided the appropriate prerequisite file exists. The double colon makes the rule "terminal", which means that its prerequisite may not be an intermediate file (*note Match-Anything Pattern Rules: Match-Anything Rules.). This pattern rule has two targets: %.tab.c %.tab.h: %.y bison -d $< This tells 'make' that the recipe 'bison -d X.y' will make both 'X.tab.c' and 'X.tab.h'. If the file 'foo' depends on the files 'parse.tab.o' and 'scan.o' and the file 'scan.o' depends on the file 'parse.tab.h', when 'parse.y' is changed, the recipe 'bison -d parse.y' will be executed only once, and the prerequisites of both 'parse.tab.o' and 'scan.o' will be satisfied. (Presumably the file 'parse.tab.o' will be recompiled from 'parse.tab.c' and the file 'scan.o' from 'scan.c', while 'foo' is linked from 'parse.tab.o', 'scan.o', and its other prerequisites, and it will execute happily ever after.)  File: make.info, Node: Automatic Variables, Next: Pattern Match, Prev: Pattern Examples, Up: Pattern Rules 10.5.3 Automatic Variables -------------------------- Suppose you are writing a pattern rule to compile a '.c' file into a '.o' file: how do you write the 'cc' command so that it operates on the right source file name? You cannot write the name in the recipe, because the name is different each time the implicit rule is applied. What you do is use a special feature of 'make', the "automatic variables". These variables have values computed afresh for each rule that is executed, based on the target and prerequisites of the rule. In this example, you would use '$@' for the object file name and '$<' for the source file name. It's very important that you recognize the limited scope in which automatic variable values are available: they only have values within the recipe. In particular, you cannot use them anywhere within the target list of a rule; they have no value there and will expand to the empty string. Also, they cannot be accessed directly within the prerequisite list of a rule. A common mistake is attempting to use '$@' within the prerequisites list; this will not work. However, there is a special feature of GNU 'make', secondary expansion (*note Secondary Expansion::), which will allow automatic variable values to be used in prerequisite lists. Here is a table of automatic variables: '$@' The file name of the target of the rule. If the target is an archive member, then '$@' is the name of the archive file. In a pattern rule that has multiple targets (*note Introduction to Pattern Rules: Pattern Intro.), '$@' is the name of whichever target caused the rule's recipe to be run. '$%' The target member name, when the target is an archive member. *Note Archives::. For example, if the target is 'foo.a(bar.o)' then '$%' is 'bar.o' and '$@' is 'foo.a'. '$%' is empty when the target is not an archive member. '$<' The name of the first prerequisite. If the target got its recipe from an implicit rule, this will be the first prerequisite added by the implicit rule (*note Implicit Rules::). '$?' The names of all the prerequisites that are newer than the target, with spaces between them. If the target does not exist, all prerequisites will be included. For prerequisites which are archive members, only the named member is used (*note Archives::). '$^' The names of all the prerequisites, with spaces between them. For prerequisites which are archive members, only the named member is used (*note Archives::). A target has only one prerequisite on each other file it depends on, no matter how many times each file is listed as a prerequisite. So if you list a prerequisite more than once for a target, the value of '$^' contains just one copy of the name. This list does *not* contain any of the order-only prerequisites; for those see the '$|' variable, below. '$+' This is like '$^', but prerequisites listed more than once are duplicated in the order they were listed in the makefile. This is primarily useful for use in linking commands where it is meaningful to repeat library file names in a particular order. '$|' The names of all the order-only prerequisites, with spaces between them. '$*' The stem with which an implicit rule matches (*note How Patterns Match: Pattern Match.). If the target is 'dir/a.foo.b' and the target pattern is 'a.%.b' then the stem is 'dir/foo'. The stem is useful for constructing names of related files. In a static pattern rule, the stem is part of the file name that matched the '%' in the target pattern. In an explicit rule, there is no stem; so '$*' cannot be determined in that way. Instead, if the target name ends with a recognized suffix (*note Old-Fashioned Suffix Rules: Suffix Rules.), '$*' is set to the target name minus the suffix. For example, if the target name is 'foo.c', then '$*' is set to 'foo', since '.c' is a suffix. GNU 'make' does this bizarre thing only for compatibility with other implementations of 'make'. You should generally avoid using '$*' except in implicit rules or static pattern rules. If the target name in an explicit rule does not end with a recognized suffix, '$*' is set to the empty string for that rule. '$?' is useful even in explicit rules when you wish to operate on only the prerequisites that have changed. For example, suppose that an archive named 'lib' is supposed to contain copies of several object files. This rule copies just the changed object files into the archive: lib: foo.o bar.o lose.o win.o ar r lib $? Of the variables listed above, four have values that are single file names, and three have values that are lists of file names. These seven have variants that get just the file's directory name or just the file name within the directory. The variant variables' names are formed by appending 'D' or 'F', respectively. The functions 'dir' and 'notdir' can be used to obtain a similar effect (*note Functions for File Names: File Name Functions.). Note, however, that the 'D' variants all omit the trailing slash which always appears in the output of the 'dir' function. Here is a table of the variants: '$(@D)' The directory part of the file name of the target, with the trailing slash removed. If the value of '$@' is 'dir/foo.o' then '$(@D)' is 'dir'. This value is '.' if '$@' does not contain a slash. '$(@F)' The file-within-directory part of the file name of the target. If the value of '$@' is 'dir/foo.o' then '$(@F)' is 'foo.o'. '$(@F)' is equivalent to '$(notdir $@)'. '$(*D)' '$(*F)' The directory part and the file-within-directory part of the stem; 'dir' and 'foo' in this example. '$(%D)' '$(%F)' The directory part and the file-within-directory part of the target archive member name. This makes sense only for archive member targets of the form 'ARCHIVE(MEMBER)' and is useful only when MEMBER may contain a directory name. (*Note Archive Members as Targets: Archive Members.) '$( #include #include #include #include #include #include int plugin_is_GPL_compatible; char * gen_tmpfile(const char *nm, int argc, char **argv) { int fd; /* Compute the size of the filename and allocate space for it. */ int len = strlen (argv[0]) + 6 + 1; char *buf = gmk_alloc (len); strcpy (buf, argv[0]); strcat (buf, "XXXXXX"); fd = mkstemp(buf); if (fd >= 0) { /* Don't leak the file descriptor. */ close (fd); return buf; } /* Failure. */ fprintf (stderr, "mkstemp(%s) failed: %s\n", buf, strerror (errno)); gmk_free (buf); return NULL; } int mk_temp_gmk_setup () { /* Register the function with make name "mk-temp". */ gmk_add_function ("mk-temp", gen_tmpfile, 1, 1, 1); return 1; } Next, we will write a makefile that can build this shared object, load it, and use it: all: @echo Temporary file: $(mk-temp tmpfile.) load mk_temp.so mk_temp.so: mk_temp.c $(CC) -shared -fPIC -o $ $< On MS-Windows, due to peculiarities of how shared objects are produced, the compiler needs to scan the "import library" produced when building 'make', typically called 'libgnumake-VERSION.dll.a', where VERSION is the version of the load object API. So the recipe to produce a shared object will look on Windows like this (assuming the API version is 1): mk_temp.dll: mk_temp.c $(CC) -shared -o $ $< -lgnumake-1 Now when you run 'make' you'll see something like: $ make cc -shared -fPIC -o mk_temp.so mk_temp.c Temporary filename: tmpfile.A7JEwd  File: make.info, Node: Integrating make, Next: Features, Prev: Extending make, Up: Top 13 Integrating GNU 'make' ************************* GNU 'make' is often one component in a larger system of tools, including integrated development environments, compiler toolchains, and others. The role of 'make' is to start commands and determine whether they succeeded or not: no special integration is needed to accomplish that. However, sometimes it is convenient to bind 'make' more tightly with other parts of the system, both higher-level (tools that invoke 'make') and lower-level (tools that 'make' invokes). * Menu: * Job Slots:: Share job slots with GNU 'make'. * Terminal Output:: Control output to terminals.  File: make.info, Node: Job Slots, Next: Terminal Output, Prev: Integrating make, Up: Integrating make 13.1 Sharing Job Slots with GNU 'make' ====================================== GNU 'make' has the ability to run multiple recipes in parallel (*note Parallel Execution: Parallel.) and to cap the total number of parallel jobs even across recursive invocations of 'make' (*note Communicating Options to a Sub-'make': Options/Recursion.). Tools that 'make' invokes which are also able to run multiple operations in parallel, either using multiple threads or multiple processes, can be enhanced to participate in GNU 'make''s job management facility to ensure that the total number of active threads/processes running on the system does not exceed the maximum number of slots provided to GNU 'make'. GNU 'make' uses a method called the "jobserver" to control the number of active jobs across recursive invocations. The actual implementation of the jobserver varies across different operating systems, but some fundamental aspects are always true. First, only command lines that 'make' understands to be recursive invocations of 'make' (*note How the 'MAKE' Variable Works: MAKE Variable.) will have access to the jobserver. When writing makefiles you must be sure to mark the command as recursive (most commonly by prefixing the command line with the '+' indicator (*note Recursive Use of 'make': Recursion.). Second, 'make' will provide information necessary for accessing the jobserver through the environment to its children, in the 'MAKEFLAGS' environment variable. Tools which want to participate in the jobserver protocol will need to parse this environment variable, as described in subsequent sections. Third, every command 'make' starts has one implicit job slot reserved for it before it starts. Any tool which wants to participate in the jobserver protocol should assume it can always run one job without having to contact the jobserver at all. Finally, it's critical that tools that participate in the jobserver protocol return the exact number of slots they obtained from the jobserver back to the jobserver before they exit, even under error conditions. Remember that the implicit job slot should *not* be returned to the jobserver! Returning too few slots means that those slots will be lost for the rest of the build process; returning too many slots means that extra slots will be available. The top-level 'make' command will print an error message at the end of the build if it detects an incorrect number of slots available in the jobserver. As an example, suppose you are implementing a linker which provides for multithreaded operation. You would like to enhance the linker so that if it is invoked by GNU 'make' it can participate in the jobserver protocol to control how many threads are used during link. First you will need to modify the linker to determine if the 'MAKEFLAGS' environment variable is set. Next you will need to parse the value of that variable to determine if the jobserver is available, and how to access it. If it is available then you can access it to obtain job slots controlling how much parallelism your tool can use. Once done your tool must return those job slots back to the jobserver. * Menu: * POSIX Jobserver:: Using the jobserver on POSIX systems. * Windows Jobserver:: Using the jobserver on Windows systems.  File: make.info, Node: POSIX Jobserver, Next: Windows Jobserver, Prev: Job Slots, Up: Job Slots 13.1.1 POSIX Jobserver Interaction ---------------------------------- On POSIX systems the jobserver is implemented as a simple UNIX pipe. The pipe will be pre-loaded with one single-character token for each available job. To obtain an extra slot you must read a single character from the jobserver pipe; to release a slot you must write a single character back into the jobserver pipe. Note that the read side of the jobserver pipe is set to "blocking" mode. To access the pipe you must parse the 'MAKEFLAGS' variable and look for the argument string '--jobserver-auth=R,W' where 'R' and 'W' are non-negative integers representing file descriptors: 'R' is the read file descriptor and 'W' is the write file descriptor. It's important that when you release the job slot, you write back the same character you read from the pipe for that slot. Don't assume that all tokens are the same character; different characters may have different meanings to GNU 'make'. The order is not important, since 'make' has no idea in what order jobs will complete anyway. There are various error conditions you must consider to ensure your implementation is robust: * Usually you will have a command-line argument controlling the parallel operation of your tool. Consider whether your tool should detect situations where both the jobserver and the command-line argument are specified, and how it should react. * If your tool determines that the '--jobserver-auth' option is available in 'MAKEFLAGS' but that the file descriptors specified are closed, this means that the calling 'make' process did not think that your tool was a recursive 'make' invocation (e.g., the command line was not prefixed with a '+' character). You should notify your users of this situation. * Your tool should also examine the first word of the 'MAKEFLAGS' variable and look for the character 'n'. If this character is present then 'make' was invoked with the '-n' option and your tool should stop without performing any operations. * Your tool should be sure to write back the tokens it read, even under error conditions. This includes not only errors in your tool but also outside influences such as interrupts ('SIGINT'), etc. You may want to install signal handlers to manage this write-back.  File: make.info, Node: Windows Jobserver, Prev: POSIX Jobserver, Up: Job Slots 13.1.2 Windows Jobserver Interaction ------------------------------------ On Windows systems the jobserver is implemented as a named semaphore. The semaphore will be set with an initial count equal to the number of available slots; to obtain a slot you must wait on the semaphore (with or without a timeout). To release a slot, release the semaphore. To access the semaphore you must parse the 'MAKEFLAGS' variable and look for the argument string '--jobserver-auth=NAME' where 'NAME' is the name of the named semaphore. Use this name with 'OpenSemaphore' to create a handle to the semaphore. There are various error conditions you must consider to ensure your implementation is robust: * Usually you will have a command-line argument controlling the parallel operation of your tool. Consider whether your tool should detect situations where both the jobserver and the command-line argument are specified, and how it should react. * Your tool should be sure to release the semaphore for the tokens it read, even under error conditions. This includes not only errors in your tool but also outside influences such as interrupts ('SIGINT'), etc. You may want to install signal handlers to manage this write-back.  File: make.info, Node: Terminal Output, Prev: Job Slots, Up: Integrating make 13.2 Synchronized Terminal Output ================================= Normally GNU 'make' will invoke all commands with access to the same standard and error outputs that 'make' itself was started with. A number of tools will detect whether the output is a terminal or not-a-terminal, and use this information to change the output style. For example if the output goes to a terminal the tool may add control characters that set color, or even change the location of the cursor. If the output is not going to a terminal then these special control characters are not emitted so that they don't corrupt log files, etc. The '--output-sync' (*note Output During Parallel Output: Parallel Output.) option will defeat the terminal detection. When output synchronization is enabled GNU 'make' arranges for all command output to be written to a file, so that its output can be written as a block without interference from other commands. This means that all tools invoked by 'make' will believe that their output is not going to be displayed on a terminal, even when it will be (because 'make' will display it there after the command is completed). In order to facilitate tools which would like to determine whether or not their output will be displayed on a terminal, GNU 'make' will set the 'MAKE_TERMOUT' and 'MAKE_TERMERR' environment variables before invoking any commands. Tools which would like to determine whether standard or error output (respectively) will be displayed on a terminal can check these environment variables to determine if they exist and contain a non-empty value. If so the tool can assume that the output will (eventually) be displayed on a terminal. If the variables are not set or have an empty value, then the tool should fall back to its normal methods of detecting whether output is going to a terminal or not. The content of the variables can be parsed to determine the type of terminal which will be used to display the output. Similarly, environments which invoke 'make' and would like to capture the output and eventually display it on a terminal (or some display which can interpret terminal control characters) can set these variables before invoking 'make'. GNU 'make' will not modify these environment variables if they already exist when it starts.  File: make.info, Node: Features, Next: Missing, Prev: Integrating make, Up: Top 14 Features of GNU 'make' ************************* Here is a summary of the features of GNU 'make', for comparison with and credit to other versions of 'make'. We consider the features of 'make' in 4.2 BSD systems as a baseline. If you are concerned with writing portable makefiles, you should not use the features of 'make' listed here, nor the ones in *note Missing::. Many features come from the version of 'make' in System V. * The 'VPATH' variable and its special meaning. *Note Searching Directories for Prerequisites: Directory Search. This feature exists in System V 'make', but is undocumented. It is documented in 4.3 BSD 'make' (which says it mimics System V's 'VPATH' feature). * Included makefiles. *Note Including Other Makefiles: Include. Allowing multiple files to be included with a single directive is a GNU extension. * Variables are read from and communicated via the environment. *Note Variables from the Environment: Environment. * Options passed through the variable 'MAKEFLAGS' to recursive invocations of 'make'. *Note Communicating Options to a Sub-'make': Options/Recursion. * The automatic variable '$%' is set to the member name in an archive reference. *Note Automatic Variables::. * The automatic variables '$@', '$*', '$<', '$%', and '$?' have corresponding forms like '$(@F)' and '$(@D)'. We have generalized this to '$^' as an obvious extension. *Note Automatic Variables::. * Substitution variable references. *Note Basics of Variable References: Reference. * The command line options '-b' and '-m', accepted and ignored. In System V 'make', these options actually do something. * Execution of recursive commands to run 'make' via the variable 'MAKE' even if '-n', '-q' or '-t' is specified. *Note Recursive Use of 'make': Recursion. * Support for suffix '.a' in suffix rules. *Note Archive Suffix Rules::. This feature is obsolete in GNU 'make', because the general feature of rule chaining (*note Chains of Implicit Rules: Chained Rules.) allows one pattern rule for installing members in an archive (*note Archive Update::) to be sufficient. * The arrangement of lines and backslash/newline combinations in recipes is retained when the recipes are printed, so they appear as they do in the makefile, except for the stripping of initial whitespace. The following features were inspired by various other versions of 'make'. In some cases it is unclear exactly which versions inspired which others. * Pattern rules using '%'. This has been implemented in several versions of 'make'. We're not sure who invented it first, but it's been spread around a bit. *Note Defining and Redefining Pattern Rules: Pattern Rules. * Rule chaining and implicit intermediate files. This was implemented by Stu Feldman in his version of 'make' for AT&T Eighth Edition Research Unix, and later by Andrew Hume of AT&T Bell Labs in his 'mk' program (where he terms it "transitive closure"). We do not really know if we got this from either of them or thought it up ourselves at the same time. *Note Chains of Implicit Rules: Chained Rules. * The automatic variable '$^' containing a list of all prerequisites of the current target. We did not invent this, but we have no idea who did. *Note Automatic Variables::. The automatic variable '$+' is a simple extension of '$^'. * The "what if" flag ('-W' in GNU 'make') was (as far as we know) invented by Andrew Hume in 'mk'. *Note Instead of Executing Recipes: Instead of Execution. * The concept of doing several things at once (parallelism) exists in many incarnations of 'make' and similar programs, though not in the System V or BSD implementations. *Note Recipe Execution: Execution. * A number of different build tools that support parallelism also support collecting output and displaying as a single block. *Note Output During Parallel Execution: Parallel Output. * Modified variable references using pattern substitution come from SunOS 4. *Note Basics of Variable References: Reference. This functionality was provided in GNU 'make' by the 'patsubst' function before the alternate syntax was implemented for compatibility with SunOS 4. It is not altogether clear who inspired whom, since GNU 'make' had 'patsubst' before SunOS 4 was released. * The special significance of '+' characters preceding recipe lines (*note Instead of Executing Recipes: Instead of Execution.) is mandated by 'IEEE Standard 1003.2-1992' (POSIX.2). * The '+=' syntax to append to the value of a variable comes from SunOS 4 'make'. *Note Appending More Text to Variables: Appending. * The syntax 'ARCHIVE(MEM1 MEM2...)' to list multiple members in a single archive file comes from SunOS 4 'make'. *Note Archive Members::. * The '-include' directive to include makefiles with no error for a nonexistent file comes from SunOS 4 'make'. (But note that SunOS 4 'make' does not allow multiple makefiles to be specified in one '-include' directive.) The same feature appears with the name 'sinclude' in SGI 'make' and perhaps others. * The '!=' shell assignment operator exists in many BSD of 'make' and is purposefully implemented here to behave identically to those implementations. * Various build management tools are implemented using scripting languages such as Perl or Python and thus provide a natural embedded scripting language, similar to GNU 'make''s integration of GNU Guile. The remaining features are inventions new in GNU 'make': * Use the '-v' or '--version' option to print version and copyright information. * Use the '-h' or '--help' option to summarize the options to 'make'. * Simply-expanded variables. *Note The Two Flavors of Variables: Flavors. * Pass command line variable assignments automatically through the variable 'MAKE' to recursive 'make' invocations. *Note Recursive Use of 'make': Recursion. * Use the '-C' or '--directory' command option to change directory. *Note Summary of Options: Options Summary. * Make verbatim variable definitions with 'define'. *Note Defining Multi-Line Variables: Multi-Line. * Declare phony targets with the special target '.PHONY'. Andrew Hume of AT&T Bell Labs implemented a similar feature with a different syntax in his 'mk' program. This seems to be a case of parallel discovery. *Note Phony Targets: Phony Targets. * Manipulate text by calling functions. *Note Functions for Transforming Text: Functions. * Use the '-o' or '--old-file' option to pretend a file's modification-time is old. *Note Avoiding Recompilation of Some Files: Avoiding Compilation. * Conditional execution. This feature has been implemented numerous times in various versions of 'make'; it seems a natural extension derived from the features of the C preprocessor and similar macro languages and is not a revolutionary concept. *Note Conditional Parts of Makefiles: Conditionals. * Specify a search path for included makefiles. *Note Including Other Makefiles: Include. * Specify extra makefiles to read with an environment variable. *Note The Variable 'MAKEFILES': MAKEFILES Variable. * Strip leading sequences of './' from file names, so that './FILE' and 'FILE' are considered to be the same file. * Use a special search method for library prerequisites written in the form '-lNAME'. *Note Directory Search for Link Libraries: Libraries/Search. * Allow suffixes for suffix rules (*note Old-Fashioned Suffix Rules: Suffix Rules.) to contain any characters. In other versions of 'make', they must begin with '.' and not contain any '/' characters. * Keep track of the current level of 'make' recursion using the variable 'MAKELEVEL'. *Note Recursive Use of 'make': Recursion. * Provide any goals given on the command line in the variable 'MAKECMDGOALS'. *Note Arguments to Specify the Goals: Goals. * Specify static pattern rules. *Note Static Pattern Rules: Static Pattern. * Provide selective 'vpath' search. *Note Searching Directories for Prerequisites: Directory Search. * Provide computed variable references. *Note Basics of Variable References: Reference. * Update makefiles. *Note How Makefiles Are Remade: Remaking Makefiles. System V 'make' has a very, very limited form of this functionality in that it will check out SCCS files for makefiles. * Various new built-in implicit rules. *Note Catalogue of Built-In Rules: Catalogue of Rules. * Load dynamic objects which can modify the behavior of 'make'. *Note Loading Dynamic Objects: Loading Objects.  File: make.info, Node: Missing, Next: Makefile Conventions, Prev: Features, Up: Top 15 Incompatibilities and Missing Features ***************************************** The 'make' programs in various other systems support a few features that are not implemented in GNU 'make'. The POSIX.2 standard ('IEEE Standard 1003.2-1992') which specifies 'make' does not require any of these features. * A target of the form 'FILE((ENTRY))' stands for a member of archive file FILE. The member is chosen, not by name, but by being an object file which defines the linker symbol ENTRY. This feature was not put into GNU 'make' because of the non-modularity of putting knowledge into 'make' of the internal format of archive file symbol tables. *Note Updating Archive Symbol Directories: Archive Symbols. * Suffixes (used in suffix rules) that end with the character '~' have a special meaning to System V 'make'; they refer to the SCCS file that corresponds to the file one would get without the '~'. For example, the suffix rule '.c~.o' would make the file 'N.o' from the SCCS file 's.N.c'. For complete coverage, a whole series of such suffix rules is required. *Note Old-Fashioned Suffix Rules: Suffix Rules. In GNU 'make', this entire series of cases is handled by two pattern rules for extraction from SCCS, in combination with the general feature of rule chaining. *Note Chains of Implicit Rules: Chained Rules. * In System V and 4.3 BSD 'make', files found by 'VPATH' search (*note Searching Directories for Prerequisites: Directory Search.) have their names changed inside recipes. We feel it is much cleaner to always use automatic variables and thus make this feature unnecessary. * In some Unix 'make's, the automatic variable '$*' appearing in the prerequisites of a rule has the amazingly strange "feature" of expanding to the full name of the _target of that rule_. We cannot imagine what went on in the minds of Unix 'make' developers to do this; it is utterly inconsistent with the normal definition of '$*'. * In some Unix 'make's, implicit rule search (*note Using Implicit Rules: Implicit Rules.) is apparently done for _all_ targets, not just those without recipes. This means you can do: foo.o: cc -c foo.c and Unix 'make' will intuit that 'foo.o' depends on 'foo.c'. We feel that such usage is broken. The prerequisite properties of 'make' are well-defined (for GNU 'make', at least), and doing such a thing simply does not fit the model. * GNU 'make' does not include any built-in implicit rules for compiling or preprocessing EFL programs. If we hear of anyone who is using EFL, we will gladly add them. * It appears that in SVR4 'make', a suffix rule can be specified with no recipe, and it is treated as if it had an empty recipe (*note Empty Recipes::). For example: .c.a: will override the built-in '.c.a' suffix rule. We feel that it is cleaner for a rule without a recipe to always simply add to the prerequisite list for the target. The above example can be easily rewritten to get the desired behavior in GNU 'make': .c.a: ; * Some versions of 'make' invoke the shell with the '-e' flag, except under '-k' (*note Testing the Compilation of a Program: Testing.). The '-e' flag tells the shell to exit as soon as any program it runs returns a nonzero status. We feel it is cleaner to write each line of the recipe to stand on its own and not require this special treatment.  File: make.info, Node: Makefile Conventions, Next: Quick Reference, Prev: Missing, Up: Top 16 Makefile Conventions *********************** This node describes conventions for writing the Makefiles for GNU programs. Using Automake will help you write a Makefile that follows these conventions. For more information on portable Makefiles, see POSIX and *note Portable Make Programming: (autoconf)Portable Make. * Menu: * Makefile Basics:: General conventions for Makefiles. * Utilities in Makefiles:: Utilities to be used in Makefiles. * Command Variables:: Variables for specifying commands. * DESTDIR:: Supporting staged installs. * Directory Variables:: Variables for installation directories. * Standard Targets:: Standard targets for users. * Install Command Categories:: Three categories of commands in the 'install' rule: normal, pre-install and post-install.  File: make.info, Node: Makefile Basics, Next: Utilities in Makefiles, Up: Makefile Conventions 16.1 General Conventions for Makefiles ====================================== Every Makefile should contain this line: SHELL = /bin/sh to avoid trouble on systems where the 'SHELL' variable might be inherited from the environment. (This is never a problem with GNU 'make'.) Different 'make' programs have incompatible suffix lists and implicit rules, and this sometimes creates confusion or misbehavior. So it is a good idea to set the suffix list explicitly using only the suffixes you need in the particular Makefile, like this: .SUFFIXES: .SUFFIXES: .c .o The first line clears out the suffix list, the second introduces all suffixes which may be subject to implicit rules in this Makefile. Don't assume that '.' is in the path for command execution. When you need to run programs that are a part of your package during the make, please make sure that it uses './' if the program is built as part of the make or '$(srcdir)/' if the file is an unchanging part of the source code. Without one of these prefixes, the current search path is used. The distinction between './' (the "build directory") and '$(srcdir)/' (the "source directory") is important because users can build in a separate directory using the '--srcdir' option to 'configure'. A rule of the form: foo.1 : foo.man sedscript sed -f sedscript foo.man > foo.1 will fail when the build directory is not the source directory, because 'foo.man' and 'sedscript' are in the source directory. When using GNU 'make', relying on 'VPATH' to find the source file will work in the case where there is a single dependency file, since the 'make' automatic variable '$<' will represent the source file wherever it is. (Many versions of 'make' set '$<' only in implicit rules.) A Makefile target like foo.o : bar.c $(CC) -I. -I$(srcdir) $(CFLAGS) -c bar.c -o foo.o should instead be written as foo.o : bar.c $(CC) -I. -I$(srcdir) $(CFLAGS) -c $< -o $@ in order to allow 'VPATH' to work correctly. When the target has multiple dependencies, using an explicit '$(srcdir)' is the easiest way to make the rule work well. For example, the target above for 'foo.1' is best written as: foo.1 : foo.man sedscript sed -f $(srcdir)/sedscript $(srcdir)/foo.man > $@ GNU distributions usually contain some files which are not source files--for example, Info files, and the output from Autoconf, Automake, Bison or Flex. Since these files normally appear in the source directory, they should always appear in the source directory, not in the build directory. So Makefile rules to update them should put the updated files in the source directory. However, if a file does not appear in the distribution, then the Makefile should not put it in the source directory, because building a program in ordinary circumstances should not modify the source directory in any way. Try to make the build and installation targets, at least (and all their subtargets) work correctly with a parallel 'make'.  File: make.info, Node: Utilities in Makefiles, Next: Command Variables, Prev: Makefile Basics, Up: Makefile Conventions 16.2 Utilities in Makefiles =========================== Write the Makefile commands (and any shell scripts, such as 'configure') to run under 'sh' (both the traditional Bourne shell and the POSIX shell), not 'csh'. Don't use any special features of 'ksh' or 'bash', or POSIX features not widely supported in traditional Bourne 'sh'. The 'configure' script and the Makefile rules for building and installation should not use any utilities directly except these: awk cat cmp cp diff echo egrep expr false grep install-info ln ls mkdir mv printf pwd rm rmdir sed sleep sort tar test touch tr true Compression programs such as 'gzip' can be used in the 'dist' rule. Generally, stick to the widely-supported (usually POSIX-specified) options and features of these programs. For example, don't use 'mkdir -p', convenient as it may be, because a few systems don't support it at all and with others, it is not safe for parallel execution. For a list of known incompatibilities, see *note Portable Shell Programming: (autoconf)Portable Shell. It is a good idea to avoid creating symbolic links in makefiles, since a few file systems don't support them. The Makefile rules for building and installation can also use compilers and related programs, but should do so via 'make' variables so that the user can substitute alternatives. Here are some of the programs we mean: ar bison cc flex install ld ldconfig lex make makeinfo ranlib texi2dvi yacc Use the following 'make' variables to run those programs: $(AR) $(BISON) $(CC) $(FLEX) $(INSTALL) $(LD) $(LDCONFIG) $(LEX) $(MAKE) $(MAKEINFO) $(RANLIB) $(TEXI2DVI) $(YACC) When you use 'ranlib' or 'ldconfig', you should make sure nothing bad happens if the system does not have the program in question. Arrange to ignore an error from that command, and print a message before the command to tell the user that failure of this command does not mean a problem. (The Autoconf 'AC_PROG_RANLIB' macro can help with this.) If you use symbolic links, you should implement a fallback for systems that don't have symbolic links. Additional utilities that can be used via Make variables are: chgrp chmod chown mknod It is ok to use other utilities in Makefile portions (or scripts) intended only for particular systems where you know those utilities exist.  File: make.info, Node: Command Variables, Next: DESTDIR, Prev: Utilities in Makefiles, Up: Makefile Conventions 16.3 Variables for Specifying Commands ====================================== Makefiles should provide variables for overriding certain commands, options, and so on. In particular, you should run most utility programs via variables. Thus, if you use Bison, have a variable named 'BISON' whose default value is set with 'BISON = bison', and refer to it with '$(BISON)' whenever you need to use Bison. File management utilities such as 'ln', 'rm', 'mv', and so on, need not be referred to through variables in this way, since users don't need to replace them with other programs. Each program-name variable should come with an options variable that is used to supply options to the program. Append 'FLAGS' to the program-name variable name to get the options variable name--for example, 'BISONFLAGS'. (The names 'CFLAGS' for the C compiler, 'YFLAGS' for yacc, and 'LFLAGS' for lex, are exceptions to this rule, but we keep them because they are standard.) Use 'CPPFLAGS' in any compilation command that runs the preprocessor, and use 'LDFLAGS' in any compilation command that does linking as well as in any direct use of 'ld'. If there are C compiler options that _must_ be used for proper compilation of certain files, do not include them in 'CFLAGS'. Users expect to be able to specify 'CFLAGS' freely themselves. Instead, arrange to pass the necessary options to the C compiler independently of 'CFLAGS', by writing them explicitly in the compilation commands or by defining an implicit rule, like this: CFLAGS = -g ALL_CFLAGS = -I. $(CFLAGS) .c.o: $(CC) -c $(CPPFLAGS) $(ALL_CFLAGS) $< Do include the '-g' option in 'CFLAGS', because that is not _required_ for proper compilation. You can consider it a default that is only recommended. If the package is set up so that it is compiled with GCC by default, then you might as well include '-O' in the default value of 'CFLAGS' as well. Put 'CFLAGS' last in the compilation command, after other variables containing compiler options, so the user can use 'CFLAGS' to override the others. 'CFLAGS' should be used in every invocation of the C compiler, both those which do compilation and those which do linking. Every Makefile should define the variable 'INSTALL', which is the basic command for installing a file into the system. Every Makefile should also define the variables 'INSTALL_PROGRAM' and 'INSTALL_DATA'. (The default for 'INSTALL_PROGRAM' should be '$(INSTALL)'; the default for 'INSTALL_DATA' should be '${INSTALL} -m 644'.) Then it should use those variables as the commands for actual installation, for executables and non-executables respectively. Minimal use of these variables is as follows: $(INSTALL_PROGRAM) foo $(bindir)/foo $(INSTALL_DATA) libfoo.a $(libdir)/libfoo.a However, it is preferable to support a 'DESTDIR' prefix on the target files, as explained in the next section. It is acceptable, but not required, to install multiple files in one command, with the final argument being a directory, as in: $(INSTALL_PROGRAM) foo bar baz $(bindir)  File: make.info, Node: DESTDIR, Next: Directory Variables, Prev: Command Variables, Up: Makefile Conventions 16.4 'DESTDIR': Support for Staged Installs =========================================== 'DESTDIR' is a variable prepended to each installed target file, like this: $(INSTALL_PROGRAM) foo $(DESTDIR)$(bindir)/foo $(INSTALL_DATA) libfoo.a $(DESTDIR)$(libdir)/libfoo.a The 'DESTDIR' variable is specified by the user on the 'make' command line as an absolute file name. For example: make DESTDIR=/tmp/stage install 'DESTDIR' should be supported only in the 'install*' and 'uninstall*' targets, as those are the only targets where it is useful. If your installation step would normally install '/usr/local/bin/foo' and '/usr/local/lib/libfoo.a', then an installation invoked as in the example above would install '/tmp/stage/usr/local/bin/foo' and '/tmp/stage/usr/local/lib/libfoo.a' instead. Prepending the variable 'DESTDIR' to each target in this way provides for "staged installs", where the installed files are not placed directly into their expected location but are instead copied into a temporary location ('DESTDIR'). However, installed files maintain their relative directory structure and any embedded file names will not be modified. You should not set the value of 'DESTDIR' in your 'Makefile' at all; then the files are installed into their expected locations by default. Also, specifying 'DESTDIR' should not change the operation of the software in any way, so its value should not be included in any file contents. 'DESTDIR' support is commonly used in package creation. It is also helpful to users who want to understand what a given package will install where, and to allow users who don't normally have permissions to install into protected areas to build and install before gaining those permissions. Finally, it can be useful with tools such as 'stow', where code is installed in one place but made to appear to be installed somewhere else using symbolic links or special mount operations. So, we strongly recommend GNU packages support 'DESTDIR', though it is not an absolute requirement.  File: make.info, Node: Directory Variables, Next: Standard Targets, Prev: DESTDIR, Up: Makefile Conventions 16.5 Variables for Installation Directories =========================================== Installation directories should always be named by variables, so it is easy to install in a nonstandard place. The standard names for these variables and the values they should have in GNU packages are described below. They are based on a standard file system layout; variants of it are used in GNU/Linux and other modern operating systems. Installers are expected to override these values when calling 'make' (e.g., 'make prefix=/usr install') or 'configure' (e.g., 'configure --prefix=/usr'). GNU packages should not try to guess which value should be appropriate for these variables on the system they are being installed onto: use the default settings specified here so that all GNU packages behave identically, allowing the installer to achieve any desired layout. All installation directories, and their parent directories, should be created (if necessary) before they are installed into. These first two variables set the root for the installation. All the other installation directories should be subdirectories of one of these two, and nothing should be directly installed into these two directories. 'prefix' A prefix used in constructing the default values of the variables listed below. The default value of 'prefix' should be '/usr/local'. When building the complete GNU system, the prefix will be empty and '/usr' will be a symbolic link to '/'. (If you are using Autoconf, write it as '@prefix@'.) Running 'make install' with a different value of 'prefix' from the one used to build the program should _not_ recompile the program. 'exec_prefix' A prefix used in constructing the default values of some of the variables listed below. The default value of 'exec_prefix' should be '$(prefix)'. (If you are using Autoconf, write it as '@exec_prefix@'.) Generally, '$(exec_prefix)' is used for directories that contain machine-specific files (such as executables and subroutine libraries), while '$(prefix)' is used directly for other directories. Running 'make install' with a different value of 'exec_prefix' from the one used to build the program should _not_ recompile the program. Executable programs are installed in one of the following directories. 'bindir' The directory for installing executable programs that users can run. This should normally be '/usr/local/bin', but write it as '$(exec_prefix)/bin'. (If you are using Autoconf, write it as '@bindir@'.) 'sbindir' The directory for installing executable programs that can be run from the shell, but are only generally useful to system administrators. This should normally be '/usr/local/sbin', but write it as '$(exec_prefix)/sbin'. (If you are using Autoconf, write it as '@sbindir@'.) 'libexecdir' The directory for installing executable programs to be run by other programs rather than by users. This directory should normally be '/usr/local/libexec', but write it as '$(exec_prefix)/libexec'. (If you are using Autoconf, write it as '@libexecdir@'.) The definition of 'libexecdir' is the same for all packages, so you should install your data in a subdirectory thereof. Most packages install their data under '$(libexecdir)/PACKAGE-NAME/', possibly within additional subdirectories thereof, such as '$(libexecdir)/PACKAGE-NAME/MACHINE/VERSION'. Data files used by the program during its execution are divided into categories in two ways. * Some files are normally modified by programs; others are never normally modified (though users may edit some of these). * Some files are architecture-independent and can be shared by all machines at a site; some are architecture-dependent and can be shared only by machines of the same kind and operating system; others may never be shared between two machines. This makes for six different possibilities. However, we want to discourage the use of architecture-dependent files, aside from object files and libraries. It is much cleaner to make other data files architecture-independent, and it is generally not hard. Here are the variables Makefiles should use to specify directories to put these various kinds of files in: 'datarootdir' The root of the directory tree for read-only architecture-independent data files. This should normally be '/usr/local/share', but write it as '$(prefix)/share'. (If you are using Autoconf, write it as '@datarootdir@'.) 'datadir''s default value is based on this variable; so are 'infodir', 'mandir', and others. 'datadir' The directory for installing idiosyncratic read-only architecture-independent data files for this program. This is usually the same place as 'datarootdir', but we use the two separate variables so that you can move these program-specific files without altering the location for Info files, man pages, etc. This should normally be '/usr/local/share', but write it as '$(datarootdir)'. (If you are using Autoconf, write it as '@datadir@'.) The definition of 'datadir' is the same for all packages, so you should install your data in a subdirectory thereof. Most packages install their data under '$(datadir)/PACKAGE-NAME/'. 'sysconfdir' The directory for installing read-only data files that pertain to a single machine-that is to say, files for configuring a host. Mailer and network configuration files, '/etc/passwd', and so forth belong here. All the files in this directory should be ordinary ASCII text files. This directory should normally be '/usr/local/etc', but write it as '$(prefix)/etc'. (If you are using Autoconf, write it as '@sysconfdir@'.) Do not install executables here in this directory (they probably belong in '$(libexecdir)' or '$(sbindir)'). Also do not install files that are modified in the normal course of their use (programs whose purpose is to change the configuration of the system excluded). Those probably belong in '$(localstatedir)'. 'sharedstatedir' The directory for installing architecture-independent data files which the programs modify while they run. This should normally be '/usr/local/com', but write it as '$(prefix)/com'. (If you are using Autoconf, write it as '@sharedstatedir@'.) 'localstatedir' The directory for installing data files which the programs modify while they run, and that pertain to one specific machine. Users should never need to modify files in this directory to configure the package's operation; put such configuration information in separate files that go in '$(datadir)' or '$(sysconfdir)'. '$(localstatedir)' should normally be '/usr/local/var', but write it as '$(prefix)/var'. (If you are using Autoconf, write it as '@localstatedir@'.) 'runstatedir' The directory for installing data files which the programs modify while they run, that pertain to one specific machine, and which need not persist longer than the execution of the program--which is generally long-lived, for example, until the next reboot. PID files for system daemons are a typical use. In addition, this directory should not be cleaned except perhaps at reboot, while the general '/tmp' ('TMPDIR') may be cleaned arbitrarily. This should normally be '/var/run', but write it as '$(localstatedir)/run'. Having it as a separate variable allows the use of '/run' if desired, for example. (If you are using Autoconf 2.70 or later, write it as '@runstatedir@'.) These variables specify the directory for installing certain specific types of files, if your program has them. Every GNU package should have Info files, so every program needs 'infodir', but not all need 'libdir' or 'lispdir'. 'includedir' The directory for installing header files to be included by user programs with the C '#include' preprocessor directive. This should normally be '/usr/local/include', but write it as '$(prefix)/include'. (If you are using Autoconf, write it as '@includedir@'.) Most compilers other than GCC do not look for header files in directory '/usr/local/include'. So installing the header files this way is only useful with GCC. Sometimes this is not a problem because some libraries are only really intended to work with GCC. But some libraries are intended to work with other compilers. They should install their header files in two places, one specified by 'includedir' and one specified by 'oldincludedir'. 'oldincludedir' The directory for installing '#include' header files for use with compilers other than GCC. This should normally be '/usr/include'. (If you are using Autoconf, you can write it as '@oldincludedir@'.) The Makefile commands should check whether the value of 'oldincludedir' is empty. If it is, they should not try to use it; they should cancel the second installation of the header files. A package should not replace an existing header in this directory unless the header came from the same package. Thus, if your Foo package provides a header file 'foo.h', then it should install the header file in the 'oldincludedir' directory if either (1) there is no 'foo.h' there or (2) the 'foo.h' that exists came from the Foo package. To tell whether 'foo.h' came from the Foo package, put a magic string in the file--part of a comment--and 'grep' for that string. 'docdir' The directory for installing documentation files (other than Info) for this package. By default, it should be '/usr/local/share/doc/YOURPKG', but it should be written as '$(datarootdir)/doc/YOURPKG'. (If you are using Autoconf, write it as '@docdir@'.) The YOURPKG subdirectory, which may include a version number, prevents collisions among files with common names, such as 'README'. 'infodir' The directory for installing the Info files for this package. By default, it should be '/usr/local/share/info', but it should be written as '$(datarootdir)/info'. (If you are using Autoconf, write it as '@infodir@'.) 'infodir' is separate from 'docdir' for compatibility with existing practice. 'htmldir' 'dvidir' 'pdfdir' 'psdir' Directories for installing documentation files in the particular format. They should all be set to '$(docdir)' by default. (If you are using Autoconf, write them as '@htmldir@', '@dvidir@', etc.) Packages which supply several translations of their documentation should install them in '$(htmldir)/'LL, '$(pdfdir)/'LL, etc. where LL is a locale abbreviation such as 'en' or 'pt_BR'. 'libdir' The directory for object files and libraries of object code. Do not install executables here, they probably ought to go in '$(libexecdir)' instead. The value of 'libdir' should normally be '/usr/local/lib', but write it as '$(exec_prefix)/lib'. (If you are using Autoconf, write it as '@libdir@'.) 'lispdir' The directory for installing any Emacs Lisp files in this package. By default, it should be '/usr/local/share/emacs/site-lisp', but it should be written as '$(datarootdir)/emacs/site-lisp'. If you are using Autoconf, write the default as '@lispdir@'. In order to make '@lispdir@' work, you need the following lines in your 'configure.ac' file: lispdir='${datarootdir}/emacs/site-lisp' AC_SUBST(lispdir) 'localedir' The directory for installing locale-specific message catalogs for this package. By default, it should be '/usr/local/share/locale', but it should be written as '$(datarootdir)/locale'. (If you are using Autoconf, write it as '@localedir@'.) This directory usually has a subdirectory per locale. Unix-style man pages are installed in one of the following: 'mandir' The top-level directory for installing the man pages (if any) for this package. It will normally be '/usr/local/share/man', but you should write it as '$(datarootdir)/man'. (If you are using Autoconf, write it as '@mandir@'.) 'man1dir' The directory for installing section 1 man pages. Write it as '$(mandir)/man1'. 'man2dir' The directory for installing section 2 man pages. Write it as '$(mandir)/man2' '...' *Don't make the primary documentation for any GNU software be a man page. Write a manual in Texinfo instead. Man pages are just for the sake of people running GNU software on Unix, which is a secondary application only.* 'manext' The file name extension for the installed man page. This should contain a period followed by the appropriate digit; it should normally be '.1'. 'man1ext' The file name extension for installed section 1 man pages. 'man2ext' The file name extension for installed section 2 man pages. '...' Use these names instead of 'manext' if the package needs to install man pages in more than one section of the manual. And finally, you should set the following variable: 'srcdir' The directory for the sources being compiled. The value of this variable is normally inserted by the 'configure' shell script. (If you are using Autoconf, use 'srcdir = @srcdir@'.) For example: # Common prefix for installation directories. # NOTE: This directory must exist when you start the install. prefix = /usr/local datarootdir = $(prefix)/share datadir = $(datarootdir) exec_prefix = $(prefix) # Where to put the executable for the command 'gcc'. bindir = $(exec_prefix)/bin # Where to put the directories used by the compiler. libexecdir = $(exec_prefix)/libexec # Where to put the Info files. infodir = $(datarootdir)/info If your program installs a large number of files into one of the standard user-specified directories, it might be useful to group them into a subdirectory particular to that program. If you do this, you should write the 'install' rule to create these subdirectories. Do not expect the user to include the subdirectory name in the value of any of the variables listed above. The idea of having a uniform set of variable names for installation directories is to enable the user to specify the exact same values for several different GNU packages. In order for this to be useful, all the packages must be designed so that they will work sensibly when the user does so. At times, not all of these variables may be implemented in the current release of Autoconf and/or Automake; but as of Autoconf 2.60, we believe all of them are. When any are missing, the descriptions here serve as specifications for what Autoconf will implement. As a programmer, you can either use a development version of Autoconf or avoid using these variables until a stable release is made which supports them.  File: make.info, Node: Standard Targets, Next: Install Command Categories, Prev: Directory Variables, Up: Makefile Conventions 16.6 Standard Targets for Users =============================== All GNU programs should have the following targets in their Makefiles: 'all' Compile the entire program. This should be the default target. This target need not rebuild any documentation files; Info files should normally be included in the distribution, and DVI (and other documentation format) files should be made only when explicitly asked for. By default, the Make rules should compile and link with '-g', so that executable programs have debugging symbols. Otherwise, you are essentially helpless in the face of a crash, and it is often far from easy to reproduce with a fresh build. 'install' Compile the program and copy the executables, libraries, and so on to the file names where they should reside for actual use. If there is a simple test to verify that a program is properly installed, this target should run that test. Do not strip executables when installing them. This helps eventual debugging that may be needed later, and nowadays disk space is cheap and dynamic loaders typically ensure debug sections are not loaded during normal execution. Users that need stripped binaries may invoke the 'install-strip' target to do that. If possible, write the 'install' target rule so that it does not modify anything in the directory where the program was built, provided 'make all' has just been done. This is convenient for building the program under one user name and installing it under another. The commands should create all the directories in which files are to be installed, if they don't already exist. This includes the directories specified as the values of the variables 'prefix' and 'exec_prefix', as well as all subdirectories that are needed. One way to do this is by means of an 'installdirs' target as described below. Use '-' before any command for installing a man page, so that 'make' will ignore any errors. This is in case there are systems that don't have the Unix man page documentation system installed. The way to install Info files is to copy them into '$(infodir)' with '$(INSTALL_DATA)' (*note Command Variables::), and then run the 'install-info' program if it is present. 'install-info' is a program that edits the Info 'dir' file to add or update the menu entry for the given Info file; it is part of the Texinfo package. Here is a sample rule to install an Info file that also tries to handle some additional situations, such as 'install-info' not being present. do-install-info: foo.info installdirs $(NORMAL_INSTALL) # Prefer an info file in . to one in srcdir. if test -f foo.info; then d=.; \ else d="$(srcdir)"; fi; \ $(INSTALL_DATA) $$d/foo.info \ "$(DESTDIR)$(infodir)/foo.info" # Run install-info only if it exists. # Use 'if' instead of just prepending '-' to the # line so we notice real errors from install-info. # Use '$(SHELL) -c' because some shells do not # fail gracefully when there is an unknown command. $(POST_INSTALL) if $(SHELL) -c 'install-info --version' \ >/dev/null 2>&1; then \ install-info --dir-file="$(DESTDIR)$(infodir)/dir" \ "$(DESTDIR)$(infodir)/foo.info"; \ else true; fi When writing the 'install' target, you must classify all the commands into three categories: normal ones, "pre-installation" commands and "post-installation" commands. *Note Install Command Categories::. 'install-html' 'install-dvi' 'install-pdf' 'install-ps' These targets install documentation in formats other than Info; they're intended to be called explicitly by the person installing the package, if that format is desired. GNU prefers Info files, so these must be installed by the 'install' target. When you have many documentation files to install, we recommend that you avoid collisions and clutter by arranging for these targets to install in subdirectories of the appropriate installation directory, such as 'htmldir'. As one example, if your package has multiple manuals, and you wish to install HTML documentation with many files (such as the "split" mode output by 'makeinfo --html'), you'll certainly want to use subdirectories, or two nodes with the same name in different manuals will overwrite each other. Please make these 'install-FORMAT' targets invoke the commands for the FORMAT target, for example, by making FORMAT a dependency. 'uninstall' Delete all the installed files--the copies that the 'install' and 'install-*' targets create. This rule should not modify the directories where compilation is done, only the directories where files are installed. The uninstallation commands are divided into three categories, just like the installation commands. *Note Install Command Categories::. 'install-strip' Like 'install', but strip the executable files while installing them. In simple cases, this target can use the 'install' target in a simple way: install-strip: $(MAKE) INSTALL_PROGRAM='$(INSTALL_PROGRAM) -s' \ install But if the package installs scripts as well as real executables, the 'install-strip' target can't just refer to the 'install' target; it has to strip the executables but not the scripts. 'install-strip' should not strip the executables in the build directory which are being copied for installation. It should only strip the copies that are installed. Normally we do not recommend stripping an executable unless you are sure the program has no bugs. However, it can be reasonable to install a stripped executable for actual execution while saving the unstripped executable elsewhere in case there is a bug. 'clean' Delete all files in the current directory that are normally created by building the program. Also delete files in other directories if they are created by this makefile. However, don't delete the files that record the configuration. Also preserve files that could be made by building, but normally aren't because the distribution comes with them. There is no need to delete parent directories that were created with 'mkdir -p', since they could have existed anyway. Delete '.dvi' files here if they are not part of the distribution. 'distclean' Delete all files in the current directory (or created by this makefile) that are created by configuring or building the program. If you have unpacked the source and built the program without creating any other files, 'make distclean' should leave only the files that were in the distribution. However, there is no need to delete parent directories that were created with 'mkdir -p', since they could have existed anyway. 'mostlyclean' Like 'clean', but may refrain from deleting a few files that people normally don't want to recompile. For example, the 'mostlyclean' target for GCC does not delete 'libgcc.a', because recompiling it is rarely necessary and takes a lot of time. 'maintainer-clean' Delete almost everything that can be reconstructed with this Makefile. This typically includes everything deleted by 'distclean', plus more: C source files produced by Bison, tags tables, Info files, and so on. The reason we say "almost everything" is that running the command 'make maintainer-clean' should not delete 'configure' even if 'configure' can be remade using a rule in the Makefile. More generally, 'make maintainer-clean' should not delete anything that needs to exist in order to run 'configure' and then begin to build the program. Also, there is no need to delete parent directories that were created with 'mkdir -p', since they could have existed anyway. These are the only exceptions; 'maintainer-clean' should delete everything else that can be rebuilt. The 'maintainer-clean' target is intended to be used by a maintainer of the package, not by ordinary users. You may need special tools to reconstruct some of the files that 'make maintainer-clean' deletes. Since these files are normally included in the distribution, we don't take care to make them easy to reconstruct. If you find you need to unpack the full distribution again, don't blame us. To help make users aware of this, the commands for the special 'maintainer-clean' target should start with these two: @echo 'This command is intended for maintainers to use; it' @echo 'deletes files that may need special tools to rebuild.' 'TAGS' Update a tags table for this program. 'info' Generate any Info files needed. The best way to write the rules is as follows: info: foo.info foo.info: foo.texi chap1.texi chap2.texi $(MAKEINFO) $(srcdir)/foo.texi You must define the variable 'MAKEINFO' in the Makefile. It should run the 'makeinfo' program, which is part of the Texinfo distribution. Normally a GNU distribution comes with Info files, and that means the Info files are present in the source directory. Therefore, the Make rule for an info file should update it in the source directory. When users build the package, ordinarily Make will not update the Info files because they will already be up to date. 'dvi' 'html' 'pdf' 'ps' Generate documentation files in the given format. These targets should always exist, but any or all can be a no-op if the given output format cannot be generated. These targets should not be dependencies of the 'all' target; the user must manually invoke them. Here's an example rule for generating DVI files from Texinfo: dvi: foo.dvi foo.dvi: foo.texi chap1.texi chap2.texi $(TEXI2DVI) $(srcdir)/foo.texi You must define the variable 'TEXI2DVI' in the Makefile. It should run the program 'texi2dvi', which is part of the Texinfo distribution. ('texi2dvi' uses TeX to do the real work of formatting. TeX is not distributed with Texinfo.) Alternatively, write only the dependencies, and allow GNU 'make' to provide the command. Here's another example, this one for generating HTML from Texinfo: html: foo.html foo.html: foo.texi chap1.texi chap2.texi $(TEXI2HTML) $(srcdir)/foo.texi Again, you would define the variable 'TEXI2HTML' in the Makefile; for example, it might run 'makeinfo --no-split --html' ('makeinfo' is part of the Texinfo distribution). 'dist' Create a distribution tar file for this program. The tar file should be set up so that the file names in the tar file start with a subdirectory name which is the name of the package it is a distribution for. This name can include the version number. For example, the distribution tar file of GCC version 1.40 unpacks into a subdirectory named 'gcc-1.40'. The easiest way to do this is to create a subdirectory appropriately named, use 'ln' or 'cp' to install the proper files in it, and then 'tar' that subdirectory. Compress the tar file with 'gzip'. For example, the actual distribution file for GCC version 1.40 is called 'gcc-1.40.tar.gz'. It is ok to support other free compression formats as well. The 'dist' target should explicitly depend on all non-source files that are in the distribution, to make sure they are up to date in the distribution. *Note Making Releases: (standards)Releases. 'check' Perform self-tests (if any). The user must build the program before running the tests, but need not install the program; you should write the self-tests so that they work when the program is built but not installed. The following targets are suggested as conventional names, for programs in which they are useful. 'installcheck' Perform installation tests (if any). The user must build and install the program before running the tests. You should not assume that '$(bindir)' is in the search path. 'installdirs' It's useful to add a target named 'installdirs' to create the directories where files are installed, and their parent directories. There is a script called 'mkinstalldirs' which is convenient for this; you can find it in the Gnulib package. You can use a rule like this: # Make sure all installation directories (e.g. $(bindir)) # actually exist by making them if necessary. installdirs: mkinstalldirs $(srcdir)/mkinstalldirs $(bindir) $(datadir) \ $(libdir) $(infodir) \ $(mandir) or, if you wish to support 'DESTDIR' (strongly encouraged), # Make sure all installation directories (e.g. $(bindir)) # actually exist by making them if necessary. installdirs: mkinstalldirs $(srcdir)/mkinstalldirs \ $(DESTDIR)$(bindir) $(DESTDIR)$(datadir) \ $(DESTDIR)$(libdir) $(DESTDIR)$(infodir) \ $(DESTDIR)$(mandir) This rule should not modify the directories where compilation is done. It should do nothing but create installation directories.  File: make.info, Node: Install Command Categories, Prev: Standard Targets, Up: Makefile Conventions 16.7 Install Command Categories =============================== When writing the 'install' target, you must classify all the commands into three categories: normal ones, "pre-installation" commands and "post-installation" commands. Normal commands move files into their proper places, and set their modes. They may not alter any files except the ones that come entirely from the package they belong to. Pre-installation and post-installation commands may alter other files; in particular, they can edit global configuration files or data bases. Pre-installation commands are typically executed before the normal commands, and post-installation commands are typically run after the normal commands. The most common use for a post-installation command is to run 'install-info'. This cannot be done with a normal command, since it alters a file (the Info directory) which does not come entirely and solely from the package being installed. It is a post-installation command because it needs to be done after the normal command which installs the package's Info files. Most programs don't need any pre-installation commands, but we have the feature just in case it is needed. To classify the commands in the 'install' rule into these three categories, insert "category lines" among them. A category line specifies the category for the commands that follow. A category line consists of a tab and a reference to a special Make variable, plus an optional comment at the end. There are three variables you can use, one for each category; the variable name specifies the category. Category lines are no-ops in ordinary execution because these three Make variables are normally undefined (and you _should not_ define them in the makefile). Here are the three possible category lines, each with a comment that explains what it means: $(PRE_INSTALL) # Pre-install commands follow. $(POST_INSTALL) # Post-install commands follow. $(NORMAL_INSTALL) # Normal commands follow. If you don't use a category line at the beginning of the 'install' rule, all the commands are classified as normal until the first category line. If you don't use any category lines, all the commands are classified as normal. These are the category lines for 'uninstall': $(PRE_UNINSTALL) # Pre-uninstall commands follow. $(POST_UNINSTALL) # Post-uninstall commands follow. $(NORMAL_UNINSTALL) # Normal commands follow. Typically, a pre-uninstall command would be used for deleting entries from the Info directory. If the 'install' or 'uninstall' target has any dependencies which act as subroutines of installation, then you should start _each_ dependency's commands with a category line, and start the main target's commands with a category line also. This way, you can ensure that each command is placed in the right category regardless of which of the dependencies actually run. Pre-installation and post-installation commands should not run any programs except for these: [ basename bash cat chgrp chmod chown cmp cp dd diff echo egrep expand expr false fgrep find getopt grep gunzip gzip hostname install install-info kill ldconfig ln ls md5sum mkdir mkfifo mknod mv printenv pwd rm rmdir sed sort tee test touch true uname xargs yes The reason for distinguishing the commands in this way is for the sake of making binary packages. Typically a binary package contains all the executables and other files that need to be installed, and has its own method of installing them--so it does not need to run the normal installation commands. But installing the binary package does need to execute the pre-installation and post-installation commands. Programs to build binary packages work by extracting the pre-installation and post-installation commands. Here is one way of extracting the pre-installation commands (the '-s' option to 'make' is needed to silence messages about entering subdirectories): make -s -n install -o all \ PRE_INSTALL=pre-install \ POST_INSTALL=post-install \ NORMAL_INSTALL=normal-install \ | gawk -f pre-install.awk where the file 'pre-install.awk' could contain this: $0 ~ /^(normal-install|post-install)[ \t]*$/ {on = 0} on {print $0} $0 ~ /^pre-install[ \t]*$/ {on = 1}  File: make.info, Node: Quick Reference, Next: Error Messages, Prev: Makefile Conventions, Up: Top Appendix A Quick Reference ************************** This appendix summarizes the directives, text manipulation functions, and special variables which GNU 'make' understands. *Note Special Targets::, *note Catalogue of Built-In Rules: Catalogue of Rules, and *note Summary of Options: Options Summary, for other summaries. Here is a summary of the directives GNU 'make' recognizes: 'define VARIABLE' 'define VARIABLE =' 'define VARIABLE :=' 'define VARIABLE ::=' 'define VARIABLE +=' 'define VARIABLE ?=' 'endef' Define multi-line variables. *Note Multi-Line::. 'undefine VARIABLE' Undefining variables. *Note Undefine Directive::. 'ifdef VARIABLE' 'ifndef VARIABLE' 'ifeq (A,B)' 'ifeq "A" "B"' 'ifeq 'A' 'B'' 'ifneq (A,B)' 'ifneq "A" "B"' 'ifneq 'A' 'B'' 'else' 'endif' Conditionally evaluate part of the makefile. *Note Conditionals::. 'include FILE' '-include FILE' 'sinclude FILE' Include another makefile. *Note Including Other Makefiles: Include. 'override VARIABLE-ASSIGNMENT' Define a variable, overriding any previous definition, even one from the command line. *Note The 'override' Directive: Override Directive. 'export' Tell 'make' to export all variables to child processes by default. *Note Communicating Variables to a Sub-'make': Variables/Recursion. 'export VARIABLE' 'export VARIABLE-ASSIGNMENT' 'unexport VARIABLE' Tell 'make' whether or not to export a particular variable to child processes. *Note Communicating Variables to a Sub-'make': Variables/Recursion. 'private VARIABLE-ASSIGNMENT' Do not allow this variable assignment to be inherited by prerequisites. *Note Suppressing Inheritance::. 'vpath PATTERN PATH' Specify a search path for files matching a '%' pattern. *Note The 'vpath' Directive: Selective Search. 'vpath PATTERN' Remove all search paths previously specified for PATTERN. 'vpath' Remove all search paths previously specified in any 'vpath' directive. Here is a summary of the built-in functions (*note Functions::): '$(subst FROM,TO,TEXT)' Replace FROM with TO in TEXT. *Note Functions for String Substitution and Analysis: Text Functions. '$(patsubst PATTERN,REPLACEMENT,TEXT)' Replace words matching PATTERN with REPLACEMENT in TEXT. *Note Functions for String Substitution and Analysis: Text Functions. '$(strip STRING)' Remove excess whitespace characters from STRING. *Note Functions for String Substitution and Analysis: Text Functions. '$(findstring FIND,TEXT)' Locate FIND in TEXT. *Note Functions for String Substitution and Analysis: Text Functions. '$(filter PATTERN...,TEXT)' Select words in TEXT that match one of the PATTERN words. *Note Functions for String Substitution and Analysis: Text Functions. '$(filter-out PATTERN...,TEXT)' Select words in TEXT that _do not_ match any of the PATTERN words. *Note Functions for String Substitution and Analysis: Text Functions. '$(sort LIST)' Sort the words in LIST lexicographically, removing duplicates. *Note Functions for String Substitution and Analysis: Text Functions. '$(word N,TEXT)' Extract the Nth word (one-origin) of TEXT. *Note Functions for String Substitution and Analysis: Text Functions. '$(words TEXT)' Count the number of words in TEXT. *Note Functions for String Substitution and Analysis: Text Functions. '$(wordlist S,E,TEXT)' Returns the list of words in TEXT from S to E. *Note Functions for String Substitution and Analysis: Text Functions. '$(firstword NAMES...)' Extract the first word of NAMES. *Note Functions for String Substitution and Analysis: Text Functions. '$(lastword NAMES...)' Extract the last word of NAMES. *Note Functions for String Substitution and Analysis: Text Functions. '$(dir NAMES...)' Extract the directory part of each file name. *Note Functions for File Names: File Name Functions. '$(notdir NAMES...)' Extract the non-directory part of each file name. *Note Functions for File Names: File Name Functions. '$(suffix NAMES...)' Extract the suffix (the last '.' and following characters) of each file name. *Note Functions for File Names: File Name Functions. '$(basename NAMES...)' Extract the base name (name without suffix) of each file name. *Note Functions for File Names: File Name Functions. '$(addsuffix SUFFIX,NAMES...)' Append SUFFIX to each word in NAMES. *Note Functions for File Names: File Name Functions. '$(addprefix PREFIX,NAMES...)' Prepend PREFIX to each word in NAMES. *Note Functions for File Names: File Name Functions. '$(join LIST1,LIST2)' Join two parallel lists of words. *Note Functions for File Names: File Name Functions. '$(wildcard PATTERN...)' Find file names matching a shell file name pattern (_not_ a '%' pattern). *Note The Function 'wildcard': Wildcard Function. '$(realpath NAMES...)' For each file name in NAMES, expand to an absolute name that does not contain any '.', '..', nor symlinks. *Note Functions for File Names: File Name Functions. '$(abspath NAMES...)' For each file name in NAMES, expand to an absolute name that does not contain any '.' or '..' components, but preserves symlinks. *Note Functions for File Names: File Name Functions. '$(error TEXT...)' When this function is evaluated, 'make' generates a fatal error with the message TEXT. *Note Functions That Control Make: Make Control Functions. '$(warning TEXT...)' When this function is evaluated, 'make' generates a warning with the message TEXT. *Note Functions That Control Make: Make Control Functions. '$(shell COMMAND)' Execute a shell command and return its output. *Note The 'shell' Function: Shell Function. '$(origin VARIABLE)' Return a string describing how the 'make' variable VARIABLE was defined. *Note The 'origin' Function: Origin Function. '$(flavor VARIABLE)' Return a string describing the flavor of the 'make' variable VARIABLE. *Note The 'flavor' Function: Flavor Function. '$(foreach VAR,WORDS,TEXT)' Evaluate TEXT with VAR bound to each word in WORDS, and concatenate the results. *Note The 'foreach' Function: Foreach Function. '$(if CONDITION,THEN-PART[,ELSE-PART])' Evaluate the condition CONDITION; if it's non-empty substitute the expansion of the THEN-PART otherwise substitute the expansion of the ELSE-PART. *Note Functions for Conditionals: Conditional Functions. '$(or CONDITION1[,CONDITION2[,CONDITION3...]])' Evaluate each condition CONDITIONN one at a time; substitute the first non-empty expansion. If all expansions are empty, substitute the empty string. *Note Functions for Conditionals: Conditional Functions. '$(and CONDITION1[,CONDITION2[,CONDITION3...]])' Evaluate each condition CONDITIONN one at a time; if any expansion results in the empty string substitute the empty string. If all expansions result in a non-empty string, substitute the expansion of the last CONDITION. *Note Functions for Conditionals: Conditional Functions. '$(call VAR,PARAM,...)' Evaluate the variable VAR replacing any references to '$(1)', '$(2)' with the first, second, etc. PARAM values. *Note The 'call' Function: Call Function. '$(eval TEXT)' Evaluate TEXT then read the results as makefile commands. Expands to the empty string. *Note The 'eval' Function: Eval Function. '$(file OP FILENAME,TEXT)' Expand the arguments, then open the file FILENAME using mode OP and write TEXT to that file. *Note The 'file' Function: File Function. '$(value VAR)' Evaluates to the contents of the variable VAR, with no expansion performed on it. *Note The 'value' Function: Value Function. Here is a summary of the automatic variables. *Note Automatic Variables::, for full information. '$@' The file name of the target. '$%' The target member name, when the target is an archive member. '$<' The name of the first prerequisite. '$?' The names of all the prerequisites that are newer than the target, with spaces between them. For prerequisites which are archive members, only the named member is used (*note Archives::). '$^' '$+' The names of all the prerequisites, with spaces between them. For prerequisites which are archive members, only the named member is used (*note Archives::). The value of '$^' omits duplicate prerequisites, while '$+' retains them and preserves their order. '$*' The stem with which an implicit rule matches (*note How Patterns Match: Pattern Match.). '$(@D)' '$(@F)' The directory part and the file-within-directory part of '$@'. '$(*D)' '$(*F)' The directory part and the file-within-directory part of '$*'. '$(%D)' '$(%F)' The directory part and the file-within-directory part of '$%'. '$( tar-`sed -e '/version_string/!d' \ -e 's/[^0-9.]*\([0-9.]*\).*/\1/' \ -e q version.c`.shar.Z .PHONY: dist dist: $(SRCS) $(AUX) echo tar-`sed \ -e '/version_string/!d' \ -e 's/[^0-9.]*\([0-9.]*\).*/\1/' \ -e q version.c` > .fname -rm -rf `cat .fname` mkdir `cat .fname` ln $(SRCS) $(AUX) `cat .fname` tar chZf `cat .fname`.tar.Z `cat .fname` -rm -rf `cat .fname` .fname tar.zoo: $(SRCS) $(AUX) -rm -rf tmp.dir -mkdir tmp.dir -rm tar.zoo for X in $(SRCS) $(AUX) ; do \ echo $$X ; \ sed 's/$$/^M/' $$X \ > tmp.dir/$$X ; done cd tmp.dir ; zoo aM ../tar.zoo * -rm -rf tmp.dir  File: make.info, Node: GNU Free Documentation License, Next: Concept Index, Prev: Complex Makefile, Up: Top Appendix D GNU Free Documentation License ***************************************** Version 1.3, 3 November 2008 Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. 0. PREAMBLE The purpose of this License is to make a manual, textbook, or other functional and useful document "free" in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others. This License is a kind of "copyleft", which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software. We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. 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If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant. The Document may contain zero Invariant Sections. If the Document does not identify any Invariant Sections then there are none. The "Cover Texts" are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice that says that the Document is released under this License. A Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words. 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It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document. 4. MODIFICATIONS You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version: A. Use in the Title Page (and on the covers, if any) a title distinct from that of the Document, and from those of previous versions (which should, if there were any, be listed in the History section of the Document). You may use the same title as a previous version if the original publisher of that version gives permission. B. List on the Title Page, as authors, one or more persons or entities responsible for authorship of the modifications in the Modified Version, together with at least five of the principal authors of the Document (all of its principal authors, if it has fewer than five), unless they release you from this requirement. C. State on the Title page the name of the publisher of the Modified Version, as the publisher. D. Preserve all the copyright notices of the Document. E. Add an appropriate copyright notice for your modifications adjacent to the other copyright notices. F. Include, immediately after the copyright notices, a license notice giving the public permission to use the Modified Version under the terms of this License, in the form shown in the Addendum below. G. Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document's license notice. H. Include an unaltered copy of this License. I. Preserve the section Entitled "History", Preserve its Title, and add to it an item stating at least the title, year, new authors, and publisher of the Modified Version as given on the Title Page. If there is no section Entitled "History" in the Document, create one stating the title, year, authors, and publisher of the Document as given on its Title Page, then add an item describing the Modified Version as stated in the previous sentence. J. Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document, and likewise the network locations given in the Document for previous versions it was based on. These may be placed in the "History" section. You may omit a network location for a work that was published at least four years before the Document itself, or if the original publisher of the version it refers to gives permission. K. For any section Entitled "Acknowledgements" or "Dedications", Preserve the Title of the section, and preserve in the section all the substance and tone of each of the contributor acknowledgements and/or dedications given therein. L. Preserve all the Invariant Sections of the Document, unaltered in their text and in their titles. Section numbers or the equivalent are not considered part of the section titles. M. Delete any section Entitled "Endorsements". Such a section may not be included in the Modified Version. N. Do not retitle any existing section to be Entitled "Endorsements" or to conflict in title with any Invariant Section. O. Preserve any Warranty Disclaimers. If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version's license notice. These titles must be distinct from any other section titles. You may add a section Entitled "Endorsements", provided it contains nothing but endorsements of your Modified Version by various parties--for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard. You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one. The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version. 5. COMBINING DOCUMENTS You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers. The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work. In the combination, you must combine any sections Entitled "History" in the various original documents, forming one section Entitled "History"; likewise combine any sections Entitled "Acknowledgements", and any sections Entitled "Dedications". You must delete all sections Entitled "Endorsements." 6. COLLECTIONS OF DOCUMENTS You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects. You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document. 7. AGGREGATION WITH INDEPENDENT WORKS A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an "aggregate" if the copyright resulting from the compilation is not used to limit the legal rights of the compilation's users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document. If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document's Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate. 8. TRANSLATION Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail. If a section in the Document is Entitled "Acknowledgements", "Dedications", or "History", the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title. 9. TERMINATION You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License. However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation. Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice. Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it. 10. FUTURE REVISIONS OF THIS LICENSE The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See . Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License "or any later version" applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy's public statement of acceptance of a version permanently authorizes you to choose that version for the Document. 11. RELICENSING "Massive Multiauthor Collaboration Site" (or "MMC Site") means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A "Massive Multiauthor Collaboration" (or "MMC") contained in the site means any set of copyrightable works thus published on the MMC site. "CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization. "Incorporate" means to publish or republish a Document, in whole or in part, as part of another Document. An MMC is "eligible for relicensing" if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008. The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing. ADDENDUM: How to use this License for your documents ==================================================== To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page: Copyright (C) YEAR YOUR NAME. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled ``GNU Free Documentation License''. If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the "with...Texts." line with this: with the Invariant Sections being LIST THEIR TITLES, with the Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST. If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation. If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.  File: make.info, Node: Concept Index, Next: Name Index, Prev: GNU Free Documentation License, Up: Top Index of Concepts ***************** [index] * Menu: * !=: Setting. (line 6) * !=, expansion: Reading Makefiles. (line 34) * # (comments), in makefile: Makefile Contents. (line 41) * # (comments), in recipes: Recipe Syntax. (line 29) * #include: Automatic Prerequisites. (line 16) * $, in function call: Syntax of Functions. (line 6) * $, in rules: Rule Syntax. (line 33) * $, in variable name: Computed Names. (line 6) * $, in variable reference: Reference. (line 6) * %, in pattern rules: Pattern Intro. (line 9) * %, quoting in patsubst: Text Functions. (line 26) * %, quoting in static pattern: Static Usage. (line 37) * %, quoting in vpath: Selective Search. (line 39) * %, quoting with \ (backslash): Selective Search. (line 39) * %, quoting with \ (backslash) <1>: Static Usage. (line 37) * %, quoting with \ (backslash) <2>: Text Functions. (line 26) * * (wildcard character): Wildcards. (line 6) * +, and define: Canned Recipes. (line 49) * +, and recipe execution: Instead of Execution. (line 67) * +, and recipes: MAKE Variable. (line 18) * +=: Appending. (line 6) * +=, expansion: Reading Makefiles. (line 34) * +=, expansion <1>: Reading Makefiles. (line 34) * ,v (RCS file extension): Catalogue of Rules. (line 163) * - (in recipes): Errors. (line 19) * -, and define: Canned Recipes. (line 49) * --always-make: Options Summary. (line 15) * --assume-new: Instead of Execution. (line 41) * --assume-new <1>: Options Summary. (line 285) * --assume-new, and recursion: Options/Recursion. (line 22) * --assume-old: Avoiding Compilation. (line 6) * --assume-old <1>: Options Summary. (line 164) * --assume-old, and recursion: Options/Recursion. (line 22) * --check-symlink-times: Options Summary. (line 145) * --debug: Options Summary. (line 43) * --directory: Recursion. (line 20) * --directory <1>: Options Summary. (line 26) * --directory, and --print-directory: -w Option. (line 20) * --directory, and recursion: Options/Recursion. (line 22) * --dry-run: Echoing. (line 18) * --dry-run <1>: Instead of Execution. (line 14) * --dry-run <2>: Options Summary. (line 155) * --environment-overrides: Options Summary. (line 85) * --eval: Options Summary. (line 90) * --file: Makefile Names. (line 23) * --file <1>: Makefile Arguments. (line 6) * --file <2>: Options Summary. (line 98) * --file, and recursion: Options/Recursion. (line 22) * --help: Options Summary. (line 104) * --ignore-errors: Errors. (line 30) * --ignore-errors <1>: Options Summary. (line 109) * --include-dir: Include. (line 53) * --include-dir <1>: Options Summary. (line 114) * --jobs: Parallel. (line 6) * --jobs <1>: Options Summary. (line 121) * --jobs, and recursion: Options/Recursion. (line 25) * --just-print: Echoing. (line 18) * --just-print <1>: Instead of Execution. (line 14) * --just-print <2>: Options Summary. (line 154) * --keep-going: Errors. (line 46) * --keep-going <1>: Testing. (line 16) * --keep-going <2>: Options Summary. (line 130) * --load-average: Parallel. (line 35) * --load-average <1>: Options Summary. (line 137) * --makefile: Makefile Names. (line 23) * --makefile <1>: Makefile Arguments. (line 6) * --makefile <2>: Options Summary. (line 99) * --max-load: Parallel. (line 35) * --max-load <1>: Options Summary. (line 138) * --new-file: Instead of Execution. (line 41) * --new-file <1>: Options Summary. (line 284) * --new-file, and recursion: Options/Recursion. (line 22) * --no-builtin-rules: Options Summary. (line 210) * --no-builtin-variables: Options Summary. (line 223) * --no-keep-going: Options Summary. (line 239) * --no-print-directory: -w Option. (line 20) * --no-print-directory <1>: Options Summary. (line 276) * --old-file: Avoiding Compilation. (line 6) * --old-file <1>: Options Summary. (line 163) * --old-file, and recursion: Options/Recursion. (line 22) * --output-sync: Parallel Output. (line 11) * --output-sync <1>: Options Summary. (line 172) * --print-data-base: Options Summary. (line 188) * --print-directory: Options Summary. (line 268) * --print-directory, and --directory: -w Option. (line 20) * --print-directory, and recursion: -w Option. (line 20) * --print-directory, disabling: -w Option. (line 20) * --question: Instead of Execution. (line 32) * --question <1>: Options Summary. (line 202) * --quiet: Echoing. (line 24) * --quiet <1>: Options Summary. (line 233) * --recon: Echoing. (line 18) * --recon <1>: Instead of Execution. (line 14) * --recon <2>: Options Summary. (line 156) * --silent: Echoing. (line 24) * --silent <1>: Options Summary. (line 232) * --stop: Options Summary. (line 240) * --touch: Instead of Execution. (line 24) * --touch <1>: Options Summary. (line 248) * --touch, and recursion: MAKE Variable. (line 35) * --trace: Options Summary. (line 255) * --version: Options Summary. (line 263) * --warn-undefined-variables: Options Summary. (line 293) * --what-if: Instead of Execution. (line 41) * --what-if <1>: Options Summary. (line 283) * -b: Options Summary. (line 9) * -B: Options Summary. (line 14) * -C: Recursion. (line 20) * -C <1>: Options Summary. (line 25) * -C, and -w: -w Option. (line 20) * -C, and recursion: Options/Recursion. (line 22) * -d: Options Summary. (line 33) * -e: Options Summary. (line 84) * -E: Options Summary. (line 89) * -e (shell flag): Automatic Prerequisites. (line 65) * -f: Makefile Names. (line 23) * -f <1>: Makefile Arguments. (line 6) * -f <2>: Options Summary. (line 97) * -f, and recursion: Options/Recursion. (line 22) * -h: Options Summary. (line 103) * -I: Include. (line 53) * -i: Errors. (line 30) * -i <1>: Options Summary. (line 108) * -I <1>: Options Summary. (line 113) * -j: Parallel. (line 6) * -j <1>: Options Summary. (line 120) * -j, and archive update: Archive Pitfalls. (line 6) * -j, and recursion: Options/Recursion. (line 25) * -k: Errors. (line 46) * -k <1>: Testing. (line 16) * -k <2>: Options Summary. (line 129) * -l: Options Summary. (line 136) * -L: Options Summary. (line 144) * -l (library search): Libraries/Search. (line 6) * -l (load average): Parallel. (line 35) * -m: Options Summary. (line 10) * -M (to compiler): Automatic Prerequisites. (line 18) * -MM (to GNU compiler): Automatic Prerequisites. (line 67) * -n: Echoing. (line 18) * -n <1>: Instead of Execution. (line 14) * -n <2>: Options Summary. (line 153) * -O: Parallel Output. (line 11) * -o: Avoiding Compilation. (line 6) * -o <1>: Options Summary. (line 162) * -O <1>: Options Summary. (line 171) * -o, and recursion: Options/Recursion. (line 22) * -p: Options Summary. (line 187) * -q: Instead of Execution. (line 32) * -q <1>: Options Summary. (line 201) * -r: Options Summary. (line 209) * -R: Options Summary. (line 222) * -s: Echoing. (line 24) * -s <1>: Options Summary. (line 231) * -S: Options Summary. (line 238) * -t: Instead of Execution. (line 24) * -t <1>: Options Summary. (line 247) * -t, and recursion: MAKE Variable. (line 35) * -v: Options Summary. (line 262) * -W: Instead of Execution. (line 41) * -w: Options Summary. (line 267) * -W <1>: Options Summary. (line 282) * -w, and -C: -w Option. (line 20) * -W, and recursion: Options/Recursion. (line 22) * -w, and recursion: -w Option. (line 20) * -w, disabling: -w Option. (line 20) * .a (archives): Archive Suffix Rules. (line 6) * .c: Catalogue of Rules. (line 35) * .C: Catalogue of Rules. (line 39) * .cc: Catalogue of Rules. (line 39) * .ch: Catalogue of Rules. (line 149) * .cpp: Catalogue of Rules. (line 39) * .d: Automatic Prerequisites. (line 80) * .def: Catalogue of Rules. (line 71) * .dvi: Catalogue of Rules. (line 149) * .f: Catalogue of Rules. (line 49) * .F: Catalogue of Rules. (line 49) * .info: Catalogue of Rules. (line 156) * .l: Catalogue of Rules. (line 121) * .LIBPATTERNS, and link libraries: Libraries/Search. (line 6) * .ln: Catalogue of Rules. (line 143) * .mod: Catalogue of Rules. (line 71) * .o: Catalogue of Rules. (line 35) * .o <1>: Catalogue of Rules. (line 83) * .ONESHELL, use of: One Shell. (line 6) * .p: Catalogue of Rules. (line 45) * .PRECIOUS intermediate files: Chained Rules. (line 56) * .r: Catalogue of Rules. (line 49) * .s: Catalogue of Rules. (line 76) * .S: Catalogue of Rules. (line 79) * .sh: Catalogue of Rules. (line 178) * .SHELLFLAGS, value of: Choosing the Shell. (line 6) * .sym: Catalogue of Rules. (line 71) * .tex: Catalogue of Rules. (line 149) * .texi: Catalogue of Rules. (line 156) * .texinfo: Catalogue of Rules. (line 156) * .txinfo: Catalogue of Rules. (line 156) * .w: Catalogue of Rules. (line 149) * .web: Catalogue of Rules. (line 149) * .y: Catalogue of Rules. (line 117) * :: rules (double-colon): Double-Colon. (line 6) * ::=: Flavors. (line 56) * ::= <1>: Setting. (line 6) * :=: Flavors. (line 56) * := <1>: Setting. (line 6) * =: Flavors. (line 10) * = <1>: Setting. (line 6) * =, expansion: Reading Makefiles. (line 34) * ? (wildcard character): Wildcards. (line 6) * ?=: Flavors. (line 135) * ?= <1>: Setting. (line 6) * ?=, expansion: Reading Makefiles. (line 34) * @ (in recipes): Echoing. (line 6) * @, and define: Canned Recipes. (line 49) * [...] (wildcard characters): Wildcards. (line 6) * \ (backslash), for continuation lines: Simple Makefile. (line 41) * \ (backslash), in recipes: Splitting Recipe Lines. (line 6) * \ (backslash), to quote %: Selective Search. (line 39) * \ (backslash), to quote % <1>: Static Usage. (line 37) * \ (backslash), to quote % <2>: Text Functions. (line 26) * __.SYMDEF: Archive Symbols. (line 6) * ~ (tilde): Wildcards. (line 11) * abspath: File Name Functions. (line 120) * algorithm for directory search: Search Algorithm. (line 6) * all (standard target): Goals. (line 73) * appending to variables: Appending. (line 6) * ar: Implicit Variables. (line 40) * archive: Archives. (line 6) * archive member targets: Archive Members. (line 6) * archive symbol directory updating: Archive Symbols. (line 6) * archive, and -j: Archive Pitfalls. (line 6) * archive, and parallel execution: Archive Pitfalls. (line 6) * archive, suffix rule for: Archive Suffix Rules. (line 6) * Arg list too long: Options/Recursion. (line 58) * arguments of functions: Syntax of Functions. (line 6) * as: Catalogue of Rules. (line 76) * as <1>: Implicit Variables. (line 43) * assembly, rule to compile: Catalogue of Rules. (line 76) * automatic generation of prerequisites: Include. (line 51) * automatic generation of prerequisites <1>: Automatic Prerequisites. (line 6) * automatic variables: Automatic Variables. (line 6) * automatic variables in prerequisites: Automatic Variables. (line 17) * backquotes: Shell Function. (line 6) * backslash (\), for continuation lines: Simple Makefile. (line 41) * backslash (\), in recipes: Splitting Recipe Lines. (line 6) * backslash (\), to quote %: Selective Search. (line 39) * backslash (\), to quote % <1>: Static Usage. (line 37) * backslash (\), to quote % <2>: Text Functions. (line 26) * backslash (\), to quote newlines: Splitting Lines. (line 6) * backslashes in pathnames and wildcard expansion: Wildcard Pitfall. (line 31) * basename: File Name Functions. (line 56) * binary packages: Install Command Categories. (line 80) * broken pipe: Parallel Input. (line 11) * bugs, reporting: Bugs. (line 6) * built-in special targets: Special Targets. (line 6) * C++, rule to compile: Catalogue of Rules. (line 39) * C, rule to compile: Catalogue of Rules. (line 35) * canned recipes: Canned Recipes. (line 6) * cc: Catalogue of Rules. (line 35) * cc <1>: Implicit Variables. (line 46) * cd (shell command): Execution. (line 12) * cd (shell command) <1>: MAKE Variable. (line 16) * chains of rules: Chained Rules. (line 6) * check (standard target): Goals. (line 115) * clean (standard target): Goals. (line 76) * clean target: Simple Makefile. (line 85) * clean target <1>: Cleanup. (line 11) * cleaning up: Cleanup. (line 6) * clobber (standard target): Goals. (line 87) * co: Catalogue of Rules. (line 163) * co <1>: Implicit Variables. (line 66) * combining rules by prerequisite: Combine By Prerequisite. (line 6) * command expansion: Shell Function. (line 6) * command line variable definitions, and recursion: Options/Recursion. (line 17) * command line variables: Overriding. (line 6) * commands, sequences of: Canned Recipes. (line 6) * comments, in makefile: Makefile Contents. (line 41) * comments, in recipes: Recipe Syntax. (line 29) * compatibility: Features. (line 6) * compatibility in exporting: Variables/Recursion. (line 104) * compilation, testing: Testing. (line 6) * computed variable name: Computed Names. (line 6) * conditional expansion: Conditional Functions. (line 6) * conditional variable assignment: Flavors. (line 135) * conditionals: Conditionals. (line 6) * continuation lines: Simple Makefile. (line 41) * controlling make: Make Control Functions. (line 6) * conventions for makefiles: Makefile Conventions. (line 6) * convert guile types: Guile Types. (line 6) * ctangle: Catalogue of Rules. (line 149) * ctangle <1>: Implicit Variables. (line 103) * cweave: Catalogue of Rules. (line 149) * cweave <1>: Implicit Variables. (line 97) * data base of make rules: Options Summary. (line 188) * deducing recipes (implicit rules): make Deduces. (line 6) * default directories for included makefiles: Include. (line 53) * default goal: How Make Works. (line 11) * default goal <1>: Rules. (line 11) * default makefile name: Makefile Names. (line 6) * default rules, last-resort: Last Resort. (line 6) * define, expansion: Reading Makefiles. (line 34) * defining variables verbatim: Multi-Line. (line 6) * deletion of target files: Errors. (line 63) * deletion of target files <1>: Interrupts. (line 6) * directive: Makefile Contents. (line 28) * directories, creating installation: Directory Variables. (line 20) * directories, printing them: -w Option. (line 6) * directories, updating archive symbol: Archive Symbols. (line 6) * directory part: File Name Functions. (line 16) * directory search (VPATH): Directory Search. (line 6) * directory search (VPATH), and implicit rules: Implicit/Search. (line 6) * directory search (VPATH), and link libraries: Libraries/Search. (line 6) * directory search (VPATH), and recipes: Recipes/Search. (line 6) * directory search algorithm: Search Algorithm. (line 6) * directory search, traditional (GPATH): Search Algorithm. (line 42) * dist (standard target): Goals. (line 107) * distclean (standard target): Goals. (line 85) * dollar sign ($), in function call: Syntax of Functions. (line 6) * dollar sign ($), in rules: Rule Syntax. (line 33) * dollar sign ($), in variable name: Computed Names. (line 6) * dollar sign ($), in variable reference: Reference. (line 6) * DOS, choosing a shell in: Choosing the Shell. (line 38) * double-colon rules: Double-Colon. (line 6) * duplicate words, removing: Text Functions. (line 155) * E2BIG: Options/Recursion. (line 58) * echoing of recipes: Echoing. (line 6) * editor: Introduction. (line 22) * Emacs (M-x compile): Errors. (line 61) * empty recipes: Empty Recipes. (line 6) * empty targets: Empty Targets. (line 6) * environment: Environment. (line 6) * environment, and recursion: Variables/Recursion. (line 6) * environment, SHELL in: Choosing the Shell. (line 12) * error, stopping on: Make Control Functions. (line 11) * errors (in recipes): Errors. (line 6) * errors with wildcards: Wildcard Pitfall. (line 6) * evaluating makefile syntax: Eval Function. (line 6) * example of loaded objects: Loaded Object Example. (line 6) * example using Guile: Guile Example. (line 6) * execution, in parallel: Parallel. (line 6) * execution, instead of: Instead of Execution. (line 6) * execution, of recipes: Execution. (line 6) * exit status (errors): Errors. (line 6) * exit status of make: Running. (line 18) * expansion, secondary: Secondary Expansion. (line 6) * explicit rule, definition of: Makefile Contents. (line 10) * explicit rule, expansion: Reading Makefiles. (line 93) * explicit rules, secondary expansion of: Secondary Expansion. (line 104) * exporting variables: Variables/Recursion. (line 6) * extensions, Guile: Guile Integration. (line 6) * extensions, load directive: load Directive. (line 6) * extensions, loading: Loading Objects. (line 6) * f77: Catalogue of Rules. (line 49) * f77 <1>: Implicit Variables. (line 57) * FDL, GNU Free Documentation License: GNU Free Documentation License. (line 6) * features of GNU make: Features. (line 6) * features, missing: Missing. (line 6) * file name functions: File Name Functions. (line 6) * file name of makefile: Makefile Names. (line 6) * file name of makefile, how to specify: Makefile Names. (line 31) * file name prefix, adding: File Name Functions. (line 78) * file name suffix: File Name Functions. (line 42) * file name suffix, adding: File Name Functions. (line 67) * file name with wildcards: Wildcards. (line 6) * file name, abspath of: File Name Functions. (line 120) * file name, basename of: File Name Functions. (line 56) * file name, directory part: File Name Functions. (line 16) * file name, nondirectory part: File Name Functions. (line 26) * file name, realpath of: File Name Functions. (line 113) * file, reading from: File Function. (line 6) * file, writing to: File Function. (line 6) * files, assuming new: Instead of Execution. (line 41) * files, assuming old: Avoiding Compilation. (line 6) * files, avoiding recompilation of: Avoiding Compilation. (line 6) * files, intermediate: Chained Rules. (line 16) * filtering out words: Text Functions. (line 133) * filtering words: Text Functions. (line 115) * finding strings: Text Functions. (line 104) * flags: Options Summary. (line 6) * flags for compilers: Implicit Variables. (line 6) * flavor of variable: Flavor Function. (line 6) * flavors of variables: Flavors. (line 6) * FORCE: Force Targets. (line 6) * force targets: Force Targets. (line 6) * Fortran, rule to compile: Catalogue of Rules. (line 49) * functions: Functions. (line 6) * functions, for controlling make: Make Control Functions. (line 6) * functions, for file names: File Name Functions. (line 6) * functions, for text: Text Functions. (line 6) * functions, syntax of: Syntax of Functions. (line 6) * functions, user defined: Call Function. (line 6) * g++: Catalogue of Rules. (line 39) * g++ <1>: Implicit Variables. (line 49) * gcc: Catalogue of Rules. (line 35) * generating prerequisites automatically: Include. (line 51) * generating prerequisites automatically <1>: Automatic Prerequisites. (line 6) * get: Catalogue of Rules. (line 172) * get <1>: Implicit Variables. (line 69) * globbing (wildcards): Wildcards. (line 6) * goal: How Make Works. (line 11) * goal, default: How Make Works. (line 11) * goal, default <1>: Rules. (line 11) * goal, how to specify: Goals. (line 6) * grouped targets: Multiple Targets. (line 61) * Guile: Guile Function. (line 6) * Guile <1>: Guile Integration. (line 6) * Guile example: Guile Example. (line 6) * guile, conversion of types: Guile Types. (line 6) * home directory: Wildcards. (line 11) * IEEE Standard 1003.2: Overview. (line 13) * ifdef, expansion: Reading Makefiles. (line 83) * ifeq, expansion: Reading Makefiles. (line 83) * ifndef, expansion: Reading Makefiles. (line 83) * ifneq, expansion: Reading Makefiles. (line 83) * implicit rule: Implicit Rules. (line 6) * implicit rule, and directory search: Implicit/Search. (line 6) * implicit rule, and VPATH: Implicit/Search. (line 6) * implicit rule, definition of: Makefile Contents. (line 16) * implicit rule, expansion: Reading Makefiles. (line 93) * implicit rule, how to use: Using Implicit. (line 6) * implicit rule, introduction to: make Deduces. (line 6) * implicit rule, predefined: Catalogue of Rules. (line 6) * implicit rule, search algorithm: Implicit Rule Search. (line 6) * implicit rules, secondary expansion of: Secondary Expansion. (line 144) * included makefiles, default directories: Include. (line 53) * including (MAKEFILES variable): MAKEFILES Variable. (line 6) * including (MAKEFILE_LIST variable): Special Variables. (line 8) * including other makefiles: Include. (line 6) * incompatibilities: Missing. (line 6) * independent targets: Multiple Targets. (line 14) * Info, rule to format: Catalogue of Rules. (line 156) * inheritance, suppressing: Suppressing Inheritance. (line 6) * input during parallel execution: Parallel Input. (line 6) * install (standard target): Goals. (line 93) * installation directories, creating: Directory Variables. (line 20) * installations, staged: DESTDIR. (line 6) * interface for loaded objects: Loaded Object API. (line 6) * intermediate files: Chained Rules. (line 16) * intermediate files, preserving: Chained Rules. (line 46) * intermediate targets, explicit: Special Targets. (line 48) * interrupt: Interrupts. (line 6) * job slots: Parallel. (line 6) * job slots, and recursion: Options/Recursion. (line 25) * job slots, sharing: Job Slots. (line 6) * jobs, limiting based on load: Parallel. (line 35) * jobserver: Job Slots. (line 16) * jobserver on POSIX: POSIX Jobserver. (line 6) * jobserver on Windows: Windows Jobserver. (line 6) * joining lists of words: File Name Functions. (line 89) * killing (interruption): Interrupts. (line 6) * last-resort default rules: Last Resort. (line 6) * ld: Catalogue of Rules. (line 83) * lex: Catalogue of Rules. (line 121) * lex <1>: Implicit Variables. (line 73) * Lex, rule to run: Catalogue of Rules. (line 121) * libraries for linking, directory search: Libraries/Search. (line 6) * library archive, suffix rule for: Archive Suffix Rules. (line 6) * limiting jobs based on load: Parallel. (line 35) * link libraries, and directory search: Libraries/Search. (line 6) * link libraries, patterns matching: Libraries/Search. (line 6) * linking, predefined rule for: Catalogue of Rules. (line 83) * lint: Catalogue of Rules. (line 143) * lint <1>: Implicit Variables. (line 80) * lint, rule to run: Catalogue of Rules. (line 143) * list of all prerequisites: Automatic Variables. (line 62) * list of changed prerequisites: Automatic Variables. (line 52) * load average: Parallel. (line 35) * load directive: load Directive. (line 6) * loaded object API: Loaded Object API. (line 6) * loaded object example: Loaded Object Example. (line 6) * loaded object licensing: Loaded Object API. (line 31) * loaded objects: Loading Objects. (line 6) * loaded objects, remaking of: Remaking Loaded Objects. (line 6) * long lines, splitting: Splitting Lines. (line 6) * loops in variable expansion: Flavors. (line 44) * lpr (shell command): Wildcard Examples. (line 21) * lpr (shell command) <1>: Empty Targets. (line 25) * m2c: Catalogue of Rules. (line 71) * m2c <1>: Implicit Variables. (line 60) * macro: Using Variables. (line 10) * make depend: Automatic Prerequisites. (line 37) * make extensions: Extending make. (line 6) * make integration: Integrating make. (line 6) * make interface to guile: Guile Interface. (line 6) * make procedures in guile: Guile Interface. (line 6) * makefile: Introduction. (line 7) * makefile name: Makefile Names. (line 6) * makefile name, how to specify: Makefile Names. (line 31) * makefile rule parts: Rule Introduction. (line 6) * makefile syntax, evaluating: Eval Function. (line 6) * makefile, and MAKEFILES variable: MAKEFILES Variable. (line 6) * makefile, conventions for: Makefile Conventions. (line 6) * makefile, how make processes: How Make Works. (line 6) * makefile, how to write: Makefiles. (line 6) * makefile, including: Include. (line 6) * makefile, overriding: Overriding Makefiles. (line 6) * makefile, reading: Reading Makefiles. (line 6) * makefile, remaking of: Remaking Makefiles. (line 6) * makefile, simple: Simple Makefile. (line 6) * makefiles, and MAKEFILE_LIST variable: Special Variables. (line 8) * makefiles, and special variables: Special Variables. (line 6) * makefiles, parsing: Parsing Makefiles. (line 6) * makeinfo: Catalogue of Rules. (line 156) * makeinfo <1>: Implicit Variables. (line 84) * match-anything rule: Match-Anything Rules. (line 6) * match-anything rule, used to override: Overriding Makefiles. (line 12) * missing features: Missing. (line 6) * mistakes with wildcards: Wildcard Pitfall. (line 6) * modified variable reference: Substitution Refs. (line 6) * Modula-2, rule to compile: Catalogue of Rules. (line 71) * mostlyclean (standard target): Goals. (line 79) * multi-line variable definition: Multi-Line. (line 6) * multiple rules for one target: Multiple Rules. (line 6) * multiple rules for one target (::): Double-Colon. (line 6) * multiple targets: Multiple Targets. (line 6) * multiple targets, in pattern rule: Pattern Intro. (line 44) * name of makefile: Makefile Names. (line 6) * name of makefile, how to specify: Makefile Names. (line 31) * nested variable reference: Computed Names. (line 6) * newline, quoting, in makefile: Simple Makefile. (line 41) * newline, quoting, in recipes: Splitting Recipe Lines. (line 6) * nondirectory part: File Name Functions. (line 26) * normal prerequisites: Prerequisite Types. (line 6) * obj: Variables Simplify. (line 20) * OBJ: Variables Simplify. (line 20) * objects: Variables Simplify. (line 14) * OBJECTS: Variables Simplify. (line 20) * objects, loaded: Loading Objects. (line 6) * objs: Variables Simplify. (line 20) * OBJS: Variables Simplify. (line 20) * old-fashioned suffix rules: Suffix Rules. (line 6) * options: Options Summary. (line 6) * options, and recursion: Options/Recursion. (line 6) * options, setting from environment: Options/Recursion. (line 81) * options, setting in makefiles: Options/Recursion. (line 81) * order of pattern rules: Pattern Match. (line 30) * order-only prerequisites: Prerequisite Types. (line 6) * origin of variable: Origin Function. (line 6) * output during parallel execution: Parallel Output. (line 6) * output during parallel execution <1>: Options Summary. (line 172) * overriding makefiles: Overriding Makefiles. (line 6) * overriding variables with arguments: Overriding. (line 6) * overriding with override: Override Directive. (line 6) * parallel execution: Parallel. (line 6) * parallel execution, and archive update: Archive Pitfalls. (line 6) * parallel execution, input during: Parallel Input. (line 6) * parallel execution, output during: Parallel Output. (line 6) * parallel execution, output during <1>: Options Summary. (line 172) * parallel execution, overriding: Special Targets. (line 141) * parallel output to terminal: Terminal Output. (line 6) * parsing makefiles: Parsing Makefiles. (line 6) * parts of makefile rule: Rule Introduction. (line 6) * Pascal, rule to compile: Catalogue of Rules. (line 45) * pattern rule: Pattern Intro. (line 6) * pattern rule, expansion: Reading Makefiles. (line 93) * pattern rules, order of: Pattern Match. (line 30) * pattern rules, static (not implicit): Static Pattern. (line 6) * pattern rules, static, syntax of: Static Usage. (line 6) * pattern-specific variables: Pattern-specific. (line 6) * pc: Catalogue of Rules. (line 45) * pc <1>: Implicit Variables. (line 63) * phony targets: Phony Targets. (line 6) * phony targets and recipe execution: Instead of Execution. (line 75) * pitfalls of wildcards: Wildcard Pitfall. (line 6) * plugin_is_GPL_compatible: Loaded Object API. (line 31) * portability: Features. (line 6) * POSIX: Overview. (line 13) * POSIX <1>: Options/Recursion. (line 61) * POSIX-conforming mode, setting: Special Targets. (line 156) * post-installation commands: Install Command Categories. (line 6) * pre-installation commands: Install Command Categories. (line 6) * precious targets: Special Targets. (line 32) * predefined rules and variables, printing: Options Summary. (line 188) * prefix, adding: File Name Functions. (line 78) * prerequisite: Rules. (line 6) * prerequisite pattern, implicit: Pattern Intro. (line 22) * prerequisite pattern, static (not implicit): Static Usage. (line 30) * prerequisite types: Prerequisite Types. (line 6) * prerequisite, expansion: Reading Makefiles. (line 93) * prerequisites: Rule Syntax. (line 47) * prerequisites, and automatic variables: Automatic Variables. (line 17) * prerequisites, automatic generation: Include. (line 51) * prerequisites, automatic generation <1>: Automatic Prerequisites. (line 6) * prerequisites, introduction to: Rule Introduction. (line 8) * prerequisites, list of all: Automatic Variables. (line 62) * prerequisites, list of changed: Automatic Variables. (line 52) * prerequisites, normal: Prerequisite Types. (line 6) * prerequisites, order-only: Prerequisite Types. (line 6) * prerequisites, varying (static pattern): Static Pattern. (line 6) * preserving intermediate files: Chained Rules. (line 46) * preserving with .PRECIOUS: Special Targets. (line 32) * preserving with .PRECIOUS <1>: Chained Rules. (line 56) * preserving with .SECONDARY: Special Targets. (line 54) * print (standard target): Goals. (line 98) * print target: Wildcard Examples. (line 21) * print target <1>: Empty Targets. (line 25) * printing directories: -w Option. (line 6) * printing messages: Make Control Functions. (line 43) * printing of recipes: Echoing. (line 6) * printing user warnings: Make Control Functions. (line 35) * problems and bugs, reporting: Bugs. (line 6) * problems with wildcards: Wildcard Pitfall. (line 6) * processing a makefile: How Make Works. (line 6) * question mode: Instead of Execution. (line 32) * quoting %, in patsubst: Text Functions. (line 26) * quoting %, in static pattern: Static Usage. (line 37) * quoting %, in vpath: Selective Search. (line 39) * quoting newline, in makefile: Simple Makefile. (line 41) * quoting newline, in recipes: Splitting Recipe Lines. (line 6) * Ratfor, rule to compile: Catalogue of Rules. (line 49) * RCS, rule to extract from: Catalogue of Rules. (line 163) * reading from a file: File Function. (line 6) * reading makefiles: Reading Makefiles. (line 6) * README: Makefile Names. (line 9) * realclean (standard target): Goals. (line 86) * realpath: File Name Functions. (line 113) * recipe: Simple Makefile. (line 74) * recipe execution, single invocation: Special Targets. (line 149) * recipe lines, single shell: One Shell. (line 6) * recipe syntax: Recipe Syntax. (line 6) * recipe, execution: Execution. (line 6) * recipes: Rule Syntax. (line 25) * recipes <1>: Recipes. (line 6) * recipes setting shell variables: Execution. (line 12) * recipes, and directory search: Recipes/Search. (line 6) * recipes, backslash (\) in: Splitting Recipe Lines. (line 6) * recipes, canned: Canned Recipes. (line 6) * recipes, comments in: Recipe Syntax. (line 29) * recipes, echoing: Echoing. (line 6) * recipes, empty: Empty Recipes. (line 6) * recipes, errors in: Errors. (line 6) * recipes, execution in parallel: Parallel. (line 6) * recipes, how to write: Recipes. (line 6) * recipes, instead of executing: Instead of Execution. (line 6) * recipes, introduction to: Rule Introduction. (line 8) * recipes, quoting newlines in: Splitting Recipe Lines. (line 6) * recipes, splitting: Splitting Recipe Lines. (line 6) * recipes, using variables in: Variables in Recipes. (line 6) * recompilation: Introduction. (line 22) * recompilation, avoiding: Avoiding Compilation. (line 6) * recording events with empty targets: Empty Targets. (line 6) * recursion: Recursion. (line 6) * recursion, and -C: Options/Recursion. (line 22) * recursion, and -f: Options/Recursion. (line 22) * recursion, and -j: Options/Recursion. (line 25) * recursion, and -o: Options/Recursion. (line 22) * recursion, and -t: MAKE Variable. (line 35) * recursion, and -W: Options/Recursion. (line 22) * recursion, and -w: -w Option. (line 20) * recursion, and command line variable definitions: Options/Recursion. (line 17) * recursion, and environment: Variables/Recursion. (line 6) * recursion, and MAKE variable: MAKE Variable. (line 6) * recursion, and MAKEFILES variable: MAKEFILES Variable. (line 15) * recursion, and options: Options/Recursion. (line 6) * recursion, and printing directories: -w Option. (line 6) * recursion, and variables: Variables/Recursion. (line 6) * recursion, level of: Variables/Recursion. (line 114) * recursive variable expansion: Using Variables. (line 6) * recursive variable expansion <1>: Flavors. (line 6) * recursively expanded variables: Flavors. (line 6) * reference to variables: Reference. (line 6) * reference to variables <1>: Advanced. (line 6) * relinking: How Make Works. (line 46) * remaking loaded objects: Remaking Loaded Objects. (line 6) * remaking makefiles: Remaking Makefiles. (line 6) * removal of target files: Errors. (line 63) * removal of target files <1>: Interrupts. (line 6) * removing duplicate words: Text Functions. (line 155) * removing targets on failure: Special Targets. (line 71) * removing whitespace from split lines: Splitting Lines. (line 40) * removing, to clean up: Cleanup. (line 6) * reporting bugs: Bugs. (line 6) * rm: Implicit Variables. (line 106) * rm (shell command): Simple Makefile. (line 85) * rm (shell command) <1>: Wildcard Examples. (line 12) * rm (shell command) <2>: Phony Targets. (line 20) * rm (shell command) <3>: Errors. (line 27) * rule prerequisites: Rule Syntax. (line 47) * rule syntax: Rule Syntax. (line 6) * rule targets: Rule Syntax. (line 18) * rule, double-colon (::): Double-Colon. (line 6) * rule, explicit, definition of: Makefile Contents. (line 10) * rule, how to write: Rules. (line 6) * rule, implicit: Implicit Rules. (line 6) * rule, implicit, and directory search: Implicit/Search. (line 6) * rule, implicit, and VPATH: Implicit/Search. (line 6) * rule, implicit, chains of: Chained Rules. (line 6) * rule, implicit, definition of: Makefile Contents. (line 16) * rule, implicit, how to use: Using Implicit. (line 6) * rule, implicit, introduction to: make Deduces. (line 6) * rule, implicit, predefined: Catalogue of Rules. (line 6) * rule, introduction to: Rule Introduction. (line 6) * rule, multiple for one target: Multiple Rules. (line 6) * rule, no recipe or prerequisites: Force Targets. (line 6) * rule, pattern: Pattern Intro. (line 6) * rule, static pattern: Static Pattern. (line 6) * rule, static pattern versus implicit: Static versus Implicit. (line 6) * rule, with multiple targets: Multiple Targets. (line 6) * rules, and $: Rule Syntax. (line 33) * s. (SCCS file prefix): Catalogue of Rules. (line 172) * SCCS, rule to extract from: Catalogue of Rules. (line 172) * search algorithm, implicit rule: Implicit Rule Search. (line 6) * search path for prerequisites (VPATH): Directory Search. (line 6) * search path for prerequisites (VPATH), and implicit rules: Implicit/Search. (line 6) * search path for prerequisites (VPATH), and link libraries: Libraries/Search. (line 6) * searching for strings: Text Functions. (line 104) * secondary expansion: Secondary Expansion. (line 6) * secondary expansion and explicit rules: Secondary Expansion. (line 104) * secondary expansion and implicit rules: Secondary Expansion. (line 144) * secondary expansion and static pattern rules: Secondary Expansion. (line 136) * secondary files: Chained Rules. (line 46) * secondary targets: Special Targets. (line 54) * sed (shell command): Automatic Prerequisites. (line 72) * selecting a word: Text Functions. (line 159) * selecting word lists: Text Functions. (line 168) * sequences of commands: Canned Recipes. (line 6) * setting options from environment: Options/Recursion. (line 81) * setting options in makefiles: Options/Recursion. (line 81) * setting variables: Setting. (line 6) * several rules for one target: Multiple Rules. (line 6) * several targets in a rule: Multiple Targets. (line 6) * shar (standard target): Goals. (line 104) * shell command, function for: Shell Function. (line 6) * shell file name pattern (in include): Include. (line 13) * shell variables, setting in recipes: Execution. (line 12) * shell wildcards (in include): Include. (line 13) * shell, choosing the: Choosing the Shell. (line 6) * SHELL, exported value: Variables/Recursion. (line 23) * SHELL, import from environment: Environment. (line 37) * shell, in DOS and Windows: Choosing the Shell. (line 38) * SHELL, MS-DOS specifics: Choosing the Shell. (line 44) * SHELL, value of: Choosing the Shell. (line 6) * signal: Interrupts. (line 6) * silent operation: Echoing. (line 6) * simple makefile: Simple Makefile. (line 6) * simple variable expansion: Using Variables. (line 6) * simplifying with variables: Variables Simplify. (line 6) * simply expanded variables: Flavors. (line 56) * sorting words: Text Functions. (line 147) * spaces, in variable values: Flavors. (line 107) * spaces, stripping: Text Functions. (line 80) * special targets: Special Targets. (line 6) * special variables: Special Variables. (line 6) * specifying makefile name: Makefile Names. (line 31) * splitting long lines: Splitting Lines. (line 6) * splitting recipes: Splitting Recipe Lines. (line 6) * staged installs: DESTDIR. (line 6) * standard input: Parallel Input. (line 6) * standards conformance: Overview. (line 13) * standards for makefiles: Makefile Conventions. (line 6) * static pattern rule: Static Pattern. (line 6) * static pattern rule, syntax of: Static Usage. (line 6) * static pattern rule, versus implicit: Static versus Implicit. (line 6) * static pattern rules, secondary expansion of: Secondary Expansion. (line 136) * stem: Static Usage. (line 17) * stem <1>: Pattern Match. (line 6) * stem, shortest: Pattern Match. (line 38) * stem, variable for: Automatic Variables. (line 78) * stopping make: Make Control Functions. (line 11) * strings, searching for: Text Functions. (line 104) * stripping whitespace: Text Functions. (line 80) * sub-make: Variables/Recursion. (line 6) * subdirectories, recursion for: Recursion. (line 6) * substitution variable reference: Substitution Refs. (line 6) * suffix rule: Suffix Rules. (line 6) * suffix rule, for archive: Archive Suffix Rules. (line 6) * suffix, adding: File Name Functions. (line 67) * suffix, function to find: File Name Functions. (line 42) * suffix, substituting in variables: Substitution Refs. (line 6) * suppressing inheritance: Suppressing Inheritance. (line 6) * switches: Options Summary. (line 6) * symbol directories, updating archive: Archive Symbols. (line 6) * syntax of recipe: Recipe Syntax. (line 6) * syntax of rules: Rule Syntax. (line 6) * tab character (in commands): Rule Syntax. (line 25) * tabs in rules: Rule Introduction. (line 21) * TAGS (standard target): Goals. (line 112) * tangle: Catalogue of Rules. (line 149) * tangle <1>: Implicit Variables. (line 100) * tar (standard target): Goals. (line 101) * target: Rules. (line 6) * target pattern, implicit: Pattern Intro. (line 9) * target pattern, static (not implicit): Static Usage. (line 17) * target, deleting on error: Errors. (line 63) * target, deleting on interrupt: Interrupts. (line 6) * target, expansion: Reading Makefiles. (line 93) * target, multiple in pattern rule: Pattern Intro. (line 44) * target, multiple rules for one: Multiple Rules. (line 6) * target, touching: Instead of Execution. (line 24) * target-specific variables: Target-specific. (line 6) * targets: Rule Syntax. (line 18) * targets without a file: Phony Targets. (line 6) * targets, built-in special: Special Targets. (line 6) * targets, empty: Empty Targets. (line 6) * targets, force: Force Targets. (line 6) * targets, grouped: Multiple Targets. (line 61) * targets, independent: Multiple Targets. (line 14) * targets, introduction to: Rule Introduction. (line 8) * targets, multiple: Multiple Targets. (line 6) * targets, phony: Phony Targets. (line 6) * terminal rule: Match-Anything Rules. (line 6) * terminal, output to: Terminal Output. (line 6) * test (standard target): Goals. (line 116) * testing compilation: Testing. (line 6) * tex: Catalogue of Rules. (line 149) * tex <1>: Implicit Variables. (line 87) * TeX, rule to run: Catalogue of Rules. (line 149) * texi2dvi: Catalogue of Rules. (line 156) * texi2dvi <1>: Implicit Variables. (line 91) * Texinfo, rule to format: Catalogue of Rules. (line 156) * tilde (~): Wildcards. (line 11) * tools, sharing job slots: Job Slots. (line 6) * touch (shell command): Wildcard Examples. (line 21) * touch (shell command) <1>: Empty Targets. (line 25) * touching files: Instead of Execution. (line 24) * traditional directory search (GPATH): Search Algorithm. (line 42) * types of prerequisites: Prerequisite Types. (line 6) * types, conversion of: Guile Types. (line 6) * undefined variables, warning message: Options Summary. (line 293) * undefining variable: Undefine Directive. (line 6) * updating archive symbol directories: Archive Symbols. (line 6) * updating loaded objects: Remaking Loaded Objects. (line 6) * updating makefiles: Remaking Makefiles. (line 6) * user defined functions: Call Function. (line 6) * value: Using Variables. (line 6) * value, how a variable gets it: Values. (line 6) * variable: Using Variables. (line 6) * variable definition: Makefile Contents. (line 22) * variable references in recipes: Variables in Recipes. (line 6) * variables: Variables Simplify. (line 6) * variables, $ in name: Computed Names. (line 6) * variables, and implicit rule: Automatic Variables. (line 6) * variables, appending to: Appending. (line 6) * variables, automatic: Automatic Variables. (line 6) * variables, command line: Overriding. (line 6) * variables, command line, and recursion: Options/Recursion. (line 17) * variables, computed names: Computed Names. (line 6) * variables, conditional assignment: Flavors. (line 135) * variables, defining verbatim: Multi-Line. (line 6) * variables, environment: Variables/Recursion. (line 6) * variables, environment <1>: Environment. (line 6) * variables, exporting: Variables/Recursion. (line 6) * variables, flavor of: Flavor Function. (line 6) * variables, flavors: Flavors. (line 6) * variables, how they get their values: Values. (line 6) * variables, how to reference: Reference. (line 6) * variables, loops in expansion: Flavors. (line 44) * variables, modified reference: Substitution Refs. (line 6) * variables, multi-line: Multi-Line. (line 6) * variables, nested references: Computed Names. (line 6) * variables, origin of: Origin Function. (line 6) * variables, overriding: Override Directive. (line 6) * variables, overriding with arguments: Overriding. (line 6) * variables, pattern-specific: Pattern-specific. (line 6) * variables, recursively expanded: Flavors. (line 6) * variables, setting: Setting. (line 6) * variables, simply expanded: Flavors. (line 56) * variables, spaces in values: Flavors. (line 107) * variables, substituting suffix in: Substitution Refs. (line 6) * variables, substitution reference: Substitution Refs. (line 6) * variables, target-specific: Target-specific. (line 6) * variables, unexpanded value: Value Function. (line 6) * variables, warning for undefined: Options Summary. (line 293) * varying prerequisites: Static Pattern. (line 6) * verbatim variable definition: Multi-Line. (line 6) * vpath: Directory Search. (line 6) * VPATH, and implicit rules: Implicit/Search. (line 6) * VPATH, and link libraries: Libraries/Search. (line 6) * warnings, printing: Make Control Functions. (line 35) * weave: Catalogue of Rules. (line 149) * weave <1>: Implicit Variables. (line 94) * Web, rule to run: Catalogue of Rules. (line 149) * what if: Instead of Execution. (line 41) * whitespace, avoiding on line split: Splitting Lines. (line 40) * whitespace, in variable values: Flavors. (line 107) * whitespace, stripping: Text Functions. (line 80) * wildcard: Wildcards. (line 6) * wildcard pitfalls: Wildcard Pitfall. (line 6) * wildcard, function: File Name Functions. (line 106) * wildcard, in archive member: Archive Members. (line 36) * wildcard, in include: Include. (line 13) * wildcards and MS-DOS/MS-Windows backslashes: Wildcard Pitfall. (line 31) * Windows, choosing a shell in: Choosing the Shell. (line 38) * word, selecting a: Text Functions. (line 159) * words, extracting first: Text Functions. (line 185) * words, extracting last: Text Functions. (line 198) * words, filtering: Text Functions. (line 115) * words, filtering out: Text Functions. (line 133) * words, finding number: Text Functions. (line 180) * words, iterating over: Foreach Function. (line 6) * words, joining lists: File Name Functions. (line 89) * words, removing duplicates: Text Functions. (line 155) * words, selecting lists of: Text Functions. (line 168) * writing recipes: Recipes. (line 6) * writing rules: Rules. (line 6) * writing to a file: File Function. (line 6) * yacc: Catalogue of Rules. (line 117) * yacc <1>: Implicit Variables. (line 77) * yacc <2>: Canned Recipes. (line 18) * Yacc, rule to run: Catalogue of Rules. (line 117)  File: make.info, Node: Name Index, Prev: Concept Index, Up: Top Index of Functions, Variables, & Directives ******************************************* [index] * Menu: * $%: Automatic Variables. (line 37) * $(%D): Automatic Variables. (line 129) * $(%F): Automatic Variables. (line 130) * $(*D): Automatic Variables. (line 124) * $(*F): Automatic Variables. (line 125) * $(+D): Automatic Variables. (line 147) * $(+F): Automatic Variables. (line 148) * $(: Last Resort. (line 23) * .DEFAULT, and empty recipes: Empty Recipes. (line 16) * .DEFAULT_GOAL (define default goal): Special Variables. (line 34) * .DELETE_ON_ERROR: Special Targets. (line 70) * .DELETE_ON_ERROR <1>: Errors. (line 63) * .EXPORT_ALL_VARIABLES: Special Targets. (line 134) * .EXPORT_ALL_VARIABLES <1>: Variables/Recursion. (line 99) * .EXTRA_PREREQS (prerequisites not added to automatic variables): Special Variables. (line 178) * .FEATURES (list of supported features): Special Variables. (line 121) * .IGNORE: Special Targets. (line 77) * .IGNORE <1>: Errors. (line 30) * .INCLUDE_DIRS (list of include directories): Special Variables. (line 174) * .INTERMEDIATE: Special Targets. (line 47) * .LIBPATTERNS: Libraries/Search. (line 6) * .LOADED: load Directive. (line 62) * .LOW_RESOLUTION_TIME: Special Targets. (line 90) * .NOTPARALLEL: Special Targets. (line 140) * .ONESHELL: Special Targets. (line 148) * .ONESHELL <1>: One Shell. (line 6) * .PHONY: Phony Targets. (line 22) * .PHONY <1>: Special Targets. (line 8) * .POSIX: Special Targets. (line 155) * .POSIX <1>: Options/Recursion. (line 61) * .PRECIOUS: Special Targets. (line 31) * .PRECIOUS <1>: Interrupts. (line 22) * .RECIPEPREFIX (change the recipe prefix character): Special Variables. (line 99) * .SECONDARY: Special Targets. (line 53) * .SECONDEXPANSION: Secondary Expansion. (line 6) * .SECONDEXPANSION <1>: Special Targets. (line 63) * .SHELLFLAGS: Choosing the Shell. (line 6) * .SHELLFLAGS <1>: Choosing the Shell. (line 87) * .SHELLSTATUS: Shell Function. (line 25) * .SILENT: Special Targets. (line 121) * .SILENT <1>: Echoing. (line 24) * .SUFFIXES: Special Targets. (line 16) * .SUFFIXES <1>: Suffix Rules. (line 61) * .VARIABLES (list of variables): Special Variables. (line 112) * /usr/gnu/include: Include. (line 53) * /usr/include: Include. (line 53) * /usr/local/include: Include. (line 53) * < (automatic variable): Automatic Variables. (line 43) * : Conditional Functions. (line 12) * ifdef: Conditional Syntax. (line 6) * ifeq: Conditional Syntax. (line 6) * ifndef: Conditional Syntax. (line 6) * ifneq: Conditional Syntax. (line 6) * include: Include. (line 6) * info: Make Control Functions. (line 43) * join: File Name Functions. (line 89) * lastword: Text Functions. (line 198) * LDFLAGS: Implicit Variables. (line 139) * LDLIBS: Implicit Variables. (line 144) * LEX: Implicit Variables. (line 72) * LFLAGS: Implicit Variables. (line 150) * libexecdir: Directory Variables. (line 70) * LINT: Implicit Variables. (line 80) * LINTFLAGS: Implicit Variables. (line 162) * load: load Directive. (line 9) * LOADLIBES: Implicit Variables. (line 144) * M2C: Implicit Variables. (line 60) * MAKE: MAKE Variable. (line 6) * MAKE <1>: Flavors. (line 88) * MAKECMDGOALS: Goals. (line 30) * Makefile: Makefile Names. (line 7) * makefile: Makefile Names. (line 7) * MAKEFILES: MAKEFILES Variable. (line 6) * MAKEFILES <1>: Variables/Recursion. (line 126) * MAKEFILE_LIST (list of parsed makefiles): Special Variables. (line 8) * MAKEFLAGS: Options/Recursion. (line 6) * MAKEINFO: Implicit Variables. (line 83) * MAKELEVEL: Variables/Recursion. (line 114) * MAKELEVEL <1>: Flavors. (line 88) * MAKEOVERRIDES: Options/Recursion. (line 50) * MAKESHELL (MS-DOS alternative to SHELL): Choosing the Shell. (line 27) * MAKE_HOST: Quick Reference. (line 348) * MAKE_RESTARTS (number of times make has restarted): Special Variables. (line 73) * MAKE_TERMERR (whether stderr is a terminal): Special Variables. (line 80) * MAKE_TERMOUT (whether stdout is a terminal): Special Variables. (line 80) * MAKE_VERSION: Quick Reference. (line 343) * MFLAGS: Options/Recursion. (line 66) * notdir: File Name Functions. (line 26) * or: Conditional Functions. (line 37) * origin: Origin Function. (line 6) * OUTPUT_OPTION: Catalogue of Rules. (line 200) * override: Override Directive. (line 6) * patsubst: Substitution Refs. (line 28) * patsubst <1>: Text Functions. (line 18) * PC: Implicit Variables. (line 63) * PFLAGS: Implicit Variables. (line 156) * prefix: Directory Variables. (line 29) * private: Suppressing Inheritance. (line 6) * realpath: File Name Functions. (line 113) * RFLAGS: Implicit Variables. (line 159) * RM: Implicit Variables. (line 106) * sbindir: Directory Variables. (line 63) * SHELL: Choosing the Shell. (line 6) * SHELL <1>: Choosing the Shell. (line 88) * shell: Shell Function. (line 6) * SHELL (recipe execution): Execution. (line 6) * sort: Text Functions. (line 147) * strip: Text Functions. (line 80) * subst: Multiple Targets. (line 39) * subst <1>: Text Functions. (line 9) * suffix: File Name Functions. (line 42) * SUFFIXES: Suffix Rules. (line 81) * TANGLE: Implicit Variables. (line 100) * TEX: Implicit Variables. (line 87) * TEXI2DVI: Implicit Variables. (line 90) * undefine: Undefine Directive. (line 6) * unexport: Variables/Recursion. (line 45) * value: Value Function. (line 6) * VPATH: Directory Search. (line 6) * VPATH <1>: General Search. (line 6) * vpath: Directory Search. (line 6) * vpath <1>: Selective Search. (line 6) * warning: Make Control Functions. (line 35) * WEAVE: Implicit Variables. (line 94) * wildcard: Wildcard Function. (line 6) * wildcard <1>: File Name Functions. (line 106) * word: Text Functions. (line 159) * wordlist: Text Functions. (line 168) * words: Text Functions. (line 180) * YACC: Implicit Variables. (line 76) * YFLAGS: Implicit Variables. (line 153)