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diff --git a/db/perl/DB_File/README b/db/perl/DB_File/README new file mode 100644 index 000000000..3e9934550 --- /dev/null +++ b/db/perl/DB_File/README @@ -0,0 +1,396 @@ + DB_File + + Version 1.78 + + 30th July 2001 + + Copyright (c) 1995-2001 Paul Marquess. All rights reserved. This + program is free software; you can redistribute it and/or modify + it under the same terms as Perl itself. + + +IMPORTANT NOTICE +================ + +If are using the locking technique described in older versions of +DB_File, please read the section called "Locking: The Trouble with fd" +in DB_File.pm immediately. The locking method has been found to be +unsafe. You risk corrupting your data if you continue to use it. + +DESCRIPTION +----------- + +DB_File is a module which allows Perl programs to make use of the +facilities provided by Berkeley DB version 1. (DB_File can be built +version 2 or 3 of Berkeley DB, but it will only support the 1.x +features), + +If you want to make use of the new features available in Berkeley DB +2.x or 3.x, use the Perl module BerkeleyDB instead. + +Berkeley DB is a C library which provides a consistent interface to a +number of database formats. DB_File provides an interface to all three +of the database types (hash, btree and recno) currently supported by +Berkeley DB. + +For further details see the documentation included at the end of the +file DB_File.pm. + +PREREQUISITES +------------- + +Before you can build DB_File you must have the following installed on +your system: + + * Perl 5.004 or greater. + + * Berkeley DB. + + The official web site for Berkeley DB is http://www.sleepycat.com. + The latest version of Berkeley DB is always available there. It + is recommended that you use the most recent version available at + the Sleepycat site. + + The one exception to this advice is where you want to use DB_File + to access database files created by a third-party application, like + Sendmail or Netscape. In these cases you must build DB_File with a + compatible version of Berkeley DB. + + If you want to use Berkeley DB 2.x, you must have version 2.3.4 + or greater. If you want to use Berkeley DB 3.x, any version will + do. For Berkeley DB 1.x, use either version 1.85 or 1.86. + + +BUILDING THE MODULE +------------------- + +Assuming you have met all the prerequisites, building the module should +be relatively straightforward. + +Step 1 : If you are running either Solaris 2.5 or HP-UX 10 and want + to use Berkeley DB version 2 or 3, read either the Solaris Notes + or HP-UX Notes sections below. If you are running Linux please + read the Linux Notes section before proceeding. + +Step 2 : Edit the file config.in to suit you local installation. + Instructions are given in the file. + +Step 3 : Build and test the module using this sequence of commands: + + perl Makefile.PL + make + make test + + + NOTE: + If you have a very old version of Berkeley DB (i.e. pre 1.85), + three of the tests in the recno test harness may fail (tests 51, + 53 and 55). You can safely ignore the errors if you're never + going to use the broken functionality (recno databases with a + modified bval). Otherwise you'll have to upgrade your DB + library. + + +INSTALLATION +------------ + + make install + + +TROUBLESHOOTING +=============== + +Here are some of the common problems people encounter when building +DB_File. + +Missing db.h or libdb.a +----------------------- + +If you get an error like this: + + cc -c -I/usr/local/include -Dbool=char -DHAS_BOOL + -O2 -DVERSION=\"1.64\" -DXS_VERSION=\"1.64\" -fpic + -I/usr/local/lib/perl5/i586-linux/5.00404/CORE -DmDB_Prefix_t=size_t + -DmDB_Hash_t=u_int32_t DB_File.c + DB_File.xs:101: db.h: No such file or directory + +or this: + + LD_RUN_PATH="/lib" cc -o blib/arch/auto/DB_File/DB_File.so -shared + -L/usr/local/lib DB_File.o -L/usr/local/lib -ldb + ld: cannot open -ldb: No such file or directory + +This symptom can imply: + + 1. You don't have Berkeley DB installed on your system at all. + Solution: get & install Berkeley DB. + + 2. You do have Berkeley DB installed, but it isn't in a standard place. + Solution: Edit config.in and set the LIB and INCLUDE variables to point + to the directories where libdb.a and db.h are installed. + + +Undefined symbol db_version +--------------------------- + +DB_File seems to have built correctly, but you get an error like this +when you run the test harness: + + $ make test + PERL_DL_NONLAZY=1 /usr/bin/perl5.00404 -I./blib/arch -I./blib/lib + -I/usr/local/lib/perl5/i586-linux/5.00404 -I/usr/local/lib/perl5 -e 'use + Test::Harness qw(&runtests $verbose); $verbose=0; runtests @ARGV;' t/*.t + t/db-btree..........Can't load './blib/arch/auto/DB_File/DB_File.so' for + module DB_File: ./blib/arch/auto/DB_File/DB_File.so: undefined symbol: + db_version at /usr/local/lib/perl5/i586-linux/5.00404/DynaLoader.pm + line 166. + + at t/db-btree.t line 21 + BEGIN failed--compilation aborted at t/db-btree.t line 21. + dubious Test returned status 2 (wstat 512, 0x200) + +This error usually happens when you have both version 1 and version +2 of Berkeley DB installed on your system and DB_File attempts to +build using the db.h for Berkeley DB version 2 and the version 1 +library. Unfortunately the two versions aren't compatible with each +other. The undefined symbol error is actually caused because Berkeley +DB version 1 doesn't have the symbol db_version. + +Solution: Setting the LIB & INCLUDE variables in config.in to point to the + correct directories can sometimes be enough to fix this + problem. If that doesn't work the easiest way to fix the + problem is to either delete or temporarily rename the copies + of db.h and libdb.a that you don't want DB_File to use. + +Incompatible versions of db.h and libdb +--------------------------------------- + +BerkeleyDB seems to have built correctly, but you get an error like this +when you run the test harness: + + $ make test + PERL_DL_NONLAZY=1 /home/paul/perl/install/bin/perl5.00560 -Iblib/arch + -Iblib/lib -I/home/paul/perl/install/5.005_60/lib/5.00560/i586-linux + -I/home/paul/perl/install/5.005_60/lib/5.00560 -e 'use Test::Harness + qw(&runtests $verbose); $verbose=0; runtests @ARGV;' t/*.t + t/db-btree.......... + DB_File needs compatible versions of libdb & db.h + you have db.h version 2.3.7 and libdb version 2.7.5 + BEGIN failed--compilation aborted at t/db-btree.t line 21. + ... + +Another variation on the theme of having two versions of Berkeley DB on +your system. + +Solution: Setting the LIB & INCLUDE variables in config.in to point to the + correct directories can sometimes be enough to fix this + problem. If that doesn't work the easiest way to fix the + problem is to either delete or temporarily rename the copies + of db.h and libdb.a that you don't want BerkeleyDB to use. + If you are running Linux, please read the Linux Notes section + below. + + +Linux Notes +----------- + +Newer versions of Linux (e.g. RedHat 6, SuSe 6) ship with a C library +that has version 2.x of Berkeley DB linked into it. This makes it +difficult to build this module with anything other than the version of +Berkeley DB that shipped with your Linux release. If you do try to use +a different version of Berkeley DB you will most likely get the error +described in the "Incompatible versions of db.h and libdb" section of +this file. + +To make matters worse, prior to Perl 5.6.1, the perl binary itself +*always* included the Berkeley DB library. + +If you want to use a newer version of Berkeley DB with this module, the +easiest solution is to use Perl 5.6.1 (or better) and Berkeley DB 3.x +(or better). + +There are two approaches you can use to get older versions of Perl to +work with specific versions of Berkeley DB. Both have their advantages +and disadvantages. + +The first approach will only work when you want to build a version of +Perl older than 5.6.1 along with Berkeley DB 3.x. If you want to use +Berkeley DB 2.x, you must use the next approach. This approach involves +rebuilding your existing version of Perl after applying an unofficial +patch. The "patches" directory in the this module's source distribution +contains a number of patch files. There is one patch file for every +stable version of Perl since 5.004. Apply the appropriate patch to your +Perl source tree before re-building and installing Perl from scratch. +For example, assuming you are in the top-level source directory for +Perl 5.6.0, the command below will apply the necessary patch. Remember +to replace the path shown below with one that points to this module's +patches directory. + + patch -p1 -N </path/to/DB_File/patches/5.6.0 + +Now rebuild & install perl. You should now have a perl binary that can +be used to build this module. Follow the instructions in "BUILDING THE +MODULE", remembering to set the INCLUDE and LIB variables in config.in. + + +The second approach will work with both Berkeley DB 2.x and 3.x. +Start by building Berkeley DB as a shared library. This is from +the Berkeley DB build instructions: + + Building Shared Libraries for the GNU GCC compiler + + If you're using gcc and there's no better shared library example for + your architecture, the following shared library build procedure will + probably work. + + Add the -fpic option to the CFLAGS value in the Makefile. + + Rebuild all of your .o files. This will create a Berkeley DB library + that contains .o files with PIC code. To build the shared library, + then take the following steps in the library build directory: + + % mkdir tmp + % cd tmp + % ar xv ../libdb.a + % gcc -shared -o libdb.so *.o + % mv libdb.so .. + % cd .. + % rm -rf tmp + + Note, you may have to change the gcc line depending on the + requirements of your system. + + The file libdb.so is your shared library + +Once you have built libdb.so, you will need to store it somewhere safe. + + cp libdb.so /usr/local/BerkeleyDB/lib + +If you now set the LD_PRELOAD environment variable to point to this +shared library, Perl will use it instead of the version of Berkeley DB +that shipped with your Linux distribution. + + export LD_PRELOAD=/usr/local/BerkeleyDB/lib/libdb.so + +Finally follow the instructions in "BUILDING THE MODULE" to build, +test and install this module. Don't forget to set the INCLUDE and LIB +variables in config.in. + +Remember, you will need to have the LD_PRELOAD variable set anytime you +want to use Perl with Berkeley DB. Also note that if you have LD_PRELOAD +permanently set it will affect ALL commands you execute. This may be a +problem if you run any commands that access a database created by the +version of Berkeley DB that shipped with your Linux distribution. + + +Solaris Notes +------------- + +If you are running Solaris 2.5, and you get this error when you run the +DB_File test harness: + + libc internal error: _rmutex_unlock: rmutex not held. + +you probably need to install a Sun patch. It has been reported that +Sun patch 103187-25 (or later revisions) fixes this problem. + +To find out if you have the patch installed, the command "showrev -p" +will display the patches that are currently installed on your system. + + +HP-UX Notes +----------- + +Some people running HP-UX 10 have reported getting an error like this +when building DB_File with the native HP-UX compiler. + + ld: (Warning) At least one PA 2.0 object file (DB_File.o) was detected. + The linked output may not run on a PA 1.x system. + ld: Invalid loader fixup for symbol "$000000A5". + +If this is the case for you, Berkeley DB needs to be recompiled with +the +z or +Z option and the resulting library placed in a .sl file. The +following steps should do the trick: + + 1: Configure the Berkeley DB distribution with the +z or +Z C compiler + flag: + + env "CFLAGS=+z" ../dist/configure ... + + 2: Edit the Berkeley DB Makefile and change: + + "libdb= libdb.a" to "libdb= libdb.sl". + + + 3: Build and install the Berkeley DB distribution as usual. + + +IRIX NOTES +---------- + +If you are running IRIX, and want to use Berkeley DB version 1, you can +get it from http://reality.sgi.com/ariel. It has the patches necessary +to compile properly on IRIX 5.3. + + +FEEDBACK +======== + +How to report a problem with DB_File. + +To help me help you, I need the following information: + + 1. The version of Perl and the operating system name and version you + are running. The *complete* output from running "perl -V" will + tell me all I need to know. Don't edit the output in any way. Note, + I want you to run "perl -V" and NOT "perl -v". + + If your perl does not understand the "-V" option it is too old. DB_File + needs Perl version 5.004 or better. + + 2. The version of DB_File you have. + If you have successfully installed DB_File, this one-liner will + tell you: + + perl -e 'use DB_File; print "DB_File ver $DB_File::VERSION\n"' + + If you haven't installed DB_File then search DB_File.pm for a line + like this: + + $VERSION = "1.20" ; + + 3. The version of Berkeley DB you are using. + If you are using a version older than 1.85, think about upgrading. One + point to note if you are considering upgrading Berkeley DB - the + file formats for 1.85, 1.86, 2.0, 3.0 & 3.1 are all different. + + If you have successfully installed DB_File, this command will display + the version of Berkeley DB it was built with: + + perl -e 'use DB_File; print "Berkeley DB ver $DB_File::db_ver\n"' + + 4. If you are having problems building DB_File, send me a complete log + of what happened. + + 5. Now the difficult one. If you think you have found a bug in DB_File + and you want me to fix it, you will *greatly* enhance the chances + of me being able to track it down by sending me a small + self-contained Perl script that illustrates the problem you are + encountering. Include a summary of what you think the problem is + and a log of what happens when you run the script, in case I can't + reproduce your problem on my system. If possible, don't have the + script dependent on an existing 20Meg database. If the script you + send me can create the database itself then that is preferred. + + I realise that in some cases this is easier said than done, so if + you can only reproduce the problem in your existing script, then + you can post me that if you want. Just don't expect me to find your + problem in a hurry, or at all. :-) + + +CHANGES +------- + +See the Changes file. + +Paul Marquess <Paul.Marquess@btinternet.com> |