all files: make most variables static and const when possible.

declare lots of functions static.

16 files changed, 164 insertions, 145 deletions

diff --git a/src/basename.c b/src/basename.c
index 767dbafc6..f8d9e17f6 100644
--- a/src/basename.c
+++ b/src/basename.c
@@ -30,9 +30,10 @@
 #include "system.h"
 
 char *basename ();
-void remove_suffix ();
 void strip_trailing_slashes ();
 
+static void remove_suffix ();
+
 void
 main (argc, argv)
      int argc;
@@ -61,7 +62,7 @@ main (argc, argv)
 /* Remove SUFFIX from the end of NAME if it is there, unless NAME
    consists entirely of SUFFIX. */
 
-void
+static void
 remove_suffix (name, suffix)
      register char *name, *suffix;
 {
diff --git a/src/date.c b/src/date.c
index bb4c5816f..8ca574e91 100644
--- a/src/date.c
+++ b/src/date.c
@@ -66,8 +66,9 @@ char *xrealloc ();
 time_t get_date ();
 time_t posixtime ();
 void error ();
-void show_date ();
-void usage ();
+
+static void show_date ();
+static void usage ();
 
 /* putenv string to use Universal Coordinated Time.
    POSIX.2 says it should be "TZ=UCT0" or "TZ=GMT0". */
@@ -147,7 +148,7 @@ main (argc, argv)
    in FORMAT, followed by a newline.  If FORMAT is NULL, use the
    standard output format (ctime style but with a timezone inserted). */
 
-void
+static void
 show_date (format, when)
      char *format;
      time_t when;
@@ -180,7 +181,7 @@ show_date (format, when)
   free (out);
 }
 
-void
+static void
 usage ()
 {
   fprintf (stderr, "\
diff --git a/src/echo.c b/src/echo.c
index cae62ce8d..b8c4e58d1 100644
--- a/src/echo.c
+++ b/src/echo.c
@@ -126,7 +126,7 @@ just_echo:
 	      register char *s = argv[0];
 	      register int c;
 
-	      while (c = *s++)
+	      while ((c = *s++))
 		{
 		  if (c == '\\' && *s)
 		    {
diff --git a/src/env.c b/src/env.c
index a9bc501df..963318023 100644
--- a/src/env.c
+++ b/src/env.c
@@ -84,14 +84,15 @@
 
 int putenv ();
 void error ();
-void usage ();
+
+static void usage ();
 
 extern char **environ;
 
 /* The name by which this program was run. */
 char *program_name;
 
-static struct option longopts[] =
+static struct option const longopts[] =
 {
   {"ignore-environment", 0, NULL, 'i'},
   {"unset", 1, NULL, 'u'},
@@ -157,7 +158,7 @@ main (argc, argv, envp)
   error (errno == ENOENT ? 127 : 126, errno, "%s", argv[optind]);
 }
 
-void
+static void
 usage ()
 {
   fprintf (stderr, "\
diff --git a/src/expr.c b/src/expr.c
index 61a6c091d..3dd913632 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -67,23 +67,27 @@ static char **args;
 /* The name this program was run with. */
 char *program_name;
 
-VALUE *docolon ();
-VALUE *eval ();
-VALUE *int_value ();
-VALUE *str_value ();
+void error ();
 char *xstrdup ();
 char *strstr ();
 char *xmalloc ();
-int isstring ();
-int nextarg ();
-int nomoreargs ();
-int null ();
-int toarith ();
-void error ();
-void freev ();
-void printv ();
-void tostring ();
-void trace ();
+
+static VALUE *docolon ();
+static VALUE *eval ();
+static VALUE *int_value ();
+static VALUE *str_value ();
+static int isstring ();
+static int nextarg ();
+static int nomoreargs ();
+static int null ();
+static int toarith ();
+static void freev ();
+static void printv ();
+static void tostring ();
+
+#ifdef EVAL_TRACE
+static void trace ();
+#endif
 
 void
 main (argc, argv)
@@ -111,7 +115,7 @@ main (argc, argv)
 
 /* Return a VALUE for I.  */
 
-VALUE *
+static VALUE *
 int_value (i)
      int i;
 {
@@ -125,7 +129,7 @@ int_value (i)
 
 /* Return a VALUE for S.  */
 
-VALUE *
+static VALUE *
 str_value (s)
      char *s;
 {
@@ -139,7 +143,7 @@ str_value (s)
 
 /* Free VALUE V, including structure components.  */
 
-void
+static void
 freev (v)
      VALUE *v;
 {
@@ -150,7 +154,7 @@ freev (v)
 
 /* Print VALUE V.  */
 
-void
+static void
 printv (v)
      VALUE *v;
 {
@@ -167,7 +171,7 @@ printv (v)
 
 /* Return nonzero if V is a null-string or zero-number.  */
 
-int
+static int
 null (v)
      VALUE *v;
 {
@@ -182,7 +186,7 @@ null (v)
 
 /* Return nonzero if V is a string value.  */
 
-int
+static int
 isstring (v)
      VALUE *v;
 {
@@ -191,7 +195,7 @@ isstring (v)
 
 /* Coerce V to a string value (can't fail).  */
 
-void
+static void
 tostring (v)
      VALUE *v;
 {
@@ -212,7 +216,7 @@ tostring (v)
 
 /* Coerce V to an integer value.  Return 1 on success, 0 on failure.  */
 
-int
+static int
 toarith (v)
      VALUE *v;
 {
@@ -247,7 +251,7 @@ toarith (v)
 /* Return nonzero if the next token matches STR exactly.
    STR must not be NULL.  */
 
-int
+static int
 nextarg (str)
      char *str;
 {
@@ -258,7 +262,7 @@ nextarg (str)
 
 /* Return nonzero if there no more tokens.  */
 
-int
+static int
 nomoreargs ()
 {
   return *args == 0;
@@ -267,6 +271,7 @@ nomoreargs ()
 /* The comparison operator handling functions.  */
 
 #define cmpf(name, rel)				\
+static						\
 int name (l, r) VALUE *l; VALUE *r;		\
 {						\
   if (isstring (l) || isstring (r))		\
@@ -278,7 +283,6 @@ int name (l, r) VALUE *l; VALUE *r;		\
  else						\
    return l->u.i rel r->u.i;			\
 }
-
 cmpf (less_than, <)
 cmpf (less_equal, <=)
 cmpf (equal, ==)
@@ -291,6 +295,7 @@ cmpf (greater_than, >)
 /* The arithmetic operator handling functions.  */
 
 #define arithf(name, op)			\
+static						\
 int name (l, r) VALUE *l; VALUE *r;		\
 {						\
   if (!toarith (l) || !toarith (r))		\
@@ -309,7 +314,7 @@ arithf (mod, %)
 #ifdef EVAL_TRACE
 /* Print evaluation trace and args remaining.  */
 
-void
+static void
 trace (fxn)
      char *fxn;
 {
@@ -326,7 +331,7 @@ trace (fxn)
    SV is the VALUE for the lhs (the string),
    PV is the VALUE for the rhs (the pattern).  */
 
-VALUE *
+static VALUE *
 docolon (sv, pv)
      VALUE *sv;
      VALUE *pv;
@@ -374,7 +379,7 @@ docolon (sv, pv)
 
 /* Handle bare operands and ( expr ) syntax.  */
 
-VALUE *
+static VALUE *
 eval7 ()
 {
   VALUE *v;
@@ -401,7 +406,7 @@ eval7 ()
 
 /* Handle match, substr, index, and length keywords.  */
 
-VALUE *
+static VALUE *
 eval6 ()
 {
   VALUE *l;
@@ -476,7 +481,7 @@ eval6 ()
 /* Handle : operator (pattern matching).
    Calls docolon to do the real work.  */
 
-VALUE *
+static VALUE *
 eval5 ()
 {
   VALUE *l;
@@ -505,7 +510,7 @@ eval5 ()
 
 /* Handle *, /, % operators.  */
 
-VALUE *
+static VALUE *
 eval4 ()
 {
   VALUE *l;
@@ -538,7 +543,7 @@ eval4 ()
 
 /* Handle +, - operators.  */
 
-VALUE *
+static VALUE *
 eval3 ()
 {
   VALUE *l;
@@ -569,7 +574,7 @@ eval3 ()
 
 /* Handle comparisons.  */
 
-VALUE *
+static VALUE *
 eval2 ()
 {
   VALUE *l;
@@ -610,7 +615,7 @@ eval2 ()
 
 /* Handle &.  */
 
-VALUE *
+static VALUE *
 eval1 ()
 {
   VALUE *l;
@@ -642,7 +647,7 @@ eval1 ()
 
 /* Handle |.  */
 
-VALUE *
+static VALUE *
 eval ()
 {
   VALUE *l;
diff --git a/src/id.c b/src/id.c
index 1c9482fc6..e7aa8835d 100644
--- a/src/id.c
+++ b/src/id.c
@@ -58,11 +58,12 @@ gid_t getegid ();
 char *xmalloc ();
 int getugroups ();
 void error ();
-void print_user ();
-void print_group ();
-void print_group_list ();
-void print_full_info ();
-void usage ();
+
+static void print_user ();
+static void print_group ();
+static void print_group_list ();
+static void print_full_info ();
+static void usage ();
 
 /* The name this program was run with. */
 char *program_name;
@@ -89,7 +90,7 @@ static gid_t rgid, egid;
 /* The number of errors encountered so far. */
 static int problems = 0;
 
-static struct option longopts[] =
+static struct option const longopts[] =
 {
   {"group", 0, NULL, 'g'},
   {"name", 0, NULL, 'n'},
@@ -173,7 +174,7 @@ main (argc, argv)
 
 /* Print the name or value of user ID UID. */
 
-void
+static void
 print_user (uid)
      int uid;
 {
@@ -194,7 +195,7 @@ print_user (uid)
 
 /* Print the name or value of group ID GID. */
 
-void
+static void
 print_group (gid)
      int gid;
 {
@@ -215,7 +216,7 @@ print_group (gid)
 
 /* Print all of the distinct groups the user is in . */
 
-void
+static void
 print_group_list (username)
      char *username;
 {
@@ -258,7 +259,7 @@ print_group_list (username)
 
 /* Print all of the info about the user's user and group IDs. */
 
-void
+static void
 print_full_info (username)
      char *username;
 {
@@ -336,7 +337,7 @@ print_full_info (username)
 #endif
 }
 
-void
+static void
 usage ()
 {
   fprintf (stderr, "\
diff --git a/src/nice.c b/src/nice.c
index 6878a3422..52d79efcf 100644
--- a/src/nice.c
+++ b/src/nice.c
@@ -26,14 +26,15 @@
 #endif
 #include "system.h"
 
-int isinteger ();
 void error ();
-void usage ();
+
+static int isinteger ();
+static void usage ();
 
 /* The name this program was run with. */
 char *program_name;
 
-static struct option longopts[] =
+static struct option const longopts[] =
 {
   {"adjustment", 1, NULL, 'n'},
   {NULL, 0, NULL, 0}
@@ -122,7 +123,7 @@ main (argc, argv)
 /* Return nonzero if S represents a (possibly signed) decimal integer,
    zero if not. */
 
-int
+static int
 isinteger (s)
      char *s;
 {
@@ -139,7 +140,7 @@ isinteger (s)
   return 1;
 }
 
-void
+static void
 usage ()
 {
   fprintf (stderr, "\
diff --git a/src/pathchk.c b/src/pathchk.c
index 33b912bdb..a5f776773 100644
--- a/src/pathchk.c
+++ b/src/pathchk.c
@@ -88,14 +88,15 @@
 #endif
 
 char *xstrdup();
-int validate_path ();
 void error ();
-void usage ();
+
+static int validate_path ();
+static void usage ();
 
 /* The name this program was run with. */
 char *program_name;
 
-static struct option longopts[] =
+static struct option const longopts[] =
 {
   {"portability", 0, NULL, 'p'},
   {NULL, 0, NULL, 0}
@@ -136,7 +137,7 @@ main (argc, argv)
 /* Each element is nonzero if the corresponding ASCII character is
    in the POSIX portable character set, and zero if it is not.
    In addition, the entry for `/' is nonzero to simplify checking. */
-static char portable_chars[] =
+static char const portable_chars[] =
 {
   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0-15 */
   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 16-31 */
@@ -158,14 +159,14 @@ static char portable_chars[] =
 
 /* If PATH contains only portable characters, return 1, else 0.  */
 
-int
+static int
 portable_chars_only (path)
      char *path;
 {
   char *p;
 
   for (p = path; *p; ++p)
-    if (portable_chars[*p] == 0)
+    if (portable_chars[(unsigned char)*p] == 0)
       {
 	error (0, 0, "path `%s' contains nonportable character `%c'",
 	       path, *p);
@@ -177,7 +178,7 @@ portable_chars_only (path)
 /* Return 1 if PATH is a usable leading directory, 0 if not,
    2 if it doesn't exist.  */
 
-int
+static int
 dir_ok (path)
      char *path;
 {
@@ -222,7 +223,7 @@ dir_ok (path)
 
    Return 0 if all of these tests are successful, 1 if any fail. */
 
-int
+static int
 validate_path (path, portability)
      char *path;
      int portability;
@@ -322,7 +323,7 @@ validate_path (path, portability)
   return 0;
 }
 
-void
+static void
 usage ()
 {
   fprintf (stderr, "\
diff --git a/src/printf.c b/src/printf.c
index 99f5f6b9a..a9979a6d8 100644
--- a/src/printf.c
+++ b/src/printf.c
@@ -59,16 +59,17 @@ unsigned long strtoul ();
 #define octtobin(c) ((c) - '0')
 
 char *xmalloc ();
-double xstrtod ();
-int print_esc ();
-int print_formatted ();
-long xstrtol ();
-unsigned long xstrtoul ();
 void error ();
-void print_direc ();
-void print_esc_char ();
-void print_esc_string ();
-void verify ();
+
+static double xstrtod ();
+static int print_esc ();
+static int print_formatted ();
+static long xstrtol ();
+static unsigned long xstrtoul ();
+static void print_direc ();
+static void print_esc_char ();
+static void print_esc_string ();
+static void verify ();
 
 /* The name this program was run with. */
 char *program_name;
@@ -112,7 +113,7 @@ main (argc, argv)
    arguments to any `%' directives.
    Return the number of elements of ARGV used.  */
 
-int
+static int
 print_formatted (format, argc, argv)
      char *format;
      int argc;
@@ -232,7 +233,7 @@ print_formatted (format, argc, argv)
    Return the number of characters in the escape sequence
    besides the backslash. */
 
-int
+static int
 print_esc (escstart)
      char *escstart;
 {
@@ -268,7 +269,7 @@ print_esc (escstart)
 
 /* Output a single-character \ escape.  */
 
-void
+static void
 print_esc_char (c)
      char c;
 {
@@ -306,7 +307,7 @@ print_esc_char (c)
 
 /* Print string STR, evaluating \ escapes. */
 
-void
+static void
 print_esc_string (str)
      char *str;
 {
@@ -322,7 +323,7 @@ print_esc_string (str)
    If FIELD_WIDTH or PRECISION is non-negative, they are args for
    '*' values in those fields. */
 
-void
+static void
 print_direc (start, length, field_width, precision, argument)
      char *start;
      int length;
@@ -422,7 +423,7 @@ print_direc (start, length, field_width, precision, argument)
   free (p);
 }
 
-unsigned long
+static unsigned long
 xstrtoul (s)
      char *s;
 {
@@ -435,7 +436,7 @@ xstrtoul (s)
   return val;
 }
 
-long
+static long
 xstrtol (s)
      char *s;
 {
@@ -448,7 +449,7 @@ xstrtol (s)
   return val;
 }
 
-double
+static double
 xstrtod (s)
      char *s;
 {
@@ -461,7 +462,7 @@ xstrtod (s)
   return val;
 }
 
-void
+static void
 verify (s, end)
      char *s, *end;
 {
diff --git a/src/sleep.c b/src/sleep.c
index 7212ba54f..1551eeaa8 100644
--- a/src/sleep.c
+++ b/src/sleep.c
@@ -19,9 +19,10 @@
 #include <sys/types.h>
 #include "system.h"
 
-long argdecode ();
 void error ();
 
+static long argdecode ();
+
 /* The name by which this program was run. */
 char *program_name;
 
@@ -49,7 +50,7 @@ main (argc, argv)
   exit (0);
 }
 
-long
+static long
 argdecode (s)
      char *s;
 {
diff --git a/src/su.c b/src/su.c
index d118f4a6a..bc33f1539 100644
--- a/src/su.c
+++ b/src/su.c
@@ -77,7 +77,7 @@
 
 #ifdef HAVE_SYSLOG_H
 #include <syslog.h>
-void log_su ();
+static void log_su ();
 #else
 #ifdef SYSLOG_SUCCESS
 #undef SYSLOG_SUCCESS
@@ -134,18 +134,19 @@ void endusershell ();
 void setusershell ();
 
 char *basename ();
-char *concat ();
 char *xmalloc ();
 char *xrealloc ();
-int correct_password ();
-int elements ();
-int restricted_shell ();
-void change_identity ();
 void error ();
-void modify_environment ();
-void run_shell ();
-void usage ();
-void xputenv ();
+
+static char *concat ();
+static int correct_password ();
+static int elements ();
+static int restricted_shell ();
+static void change_identity ();
+static void modify_environment ();
+static void run_shell ();
+static void usage ();
+static void xputenv ();
 
 extern char **environ;
 
@@ -161,7 +162,7 @@ static int simulate_login;
 /* If nonzero, change some environment vars to indicate the user su'd to.  */
 static int change_environment;
 
-static struct option longopts[] =
+static struct option const longopts[] =
 {
   {"command", 1, 0, 'c'},
   {"fast", 0, &fast_startup, 1},
@@ -272,7 +273,7 @@ main (argc, argv)
    0 if not.  Return 1 without asking for a password if run by UID 0
    or if PW has an empty password.  */
 
-int
+static int
 correct_password (pw)
      struct passwd *pw;
 {
@@ -300,7 +301,7 @@ correct_password (pw)
 /* Update `environ' for the new shell based on PW, with SHELL being
    the value for the SHELL environment variable.  */
 
-void
+static void
 modify_environment (pw, shell)
      struct passwd *pw;
      char *shell;
@@ -342,7 +343,7 @@ modify_environment (pw, shell)
 
 /* Become the user and group(s) specified by PW.  */
 
-void
+static void
 change_identity (pw)
      struct passwd *pw;
 {
@@ -363,7 +364,7 @@ change_identity (pw)
    If ADDITIONAL_ARGS is nonzero, pass it to the shell as more
    arguments.  */
 
-void
+static void
 run_shell (shell, command, additional_args)
      char *shell;
      char *command;
@@ -404,7 +405,7 @@ run_shell (shell, command, additional_args)
 /* Log the fact that someone has run su to the user given by PW;
    if SUCCESSFUL is nonzero, they gave the correct password, etc.  */
 
-void
+static void
 log_su (pw, successful)
      struct passwd *pw;
      int successful;
@@ -448,14 +449,14 @@ log_su (pw, successful)
 /* Return 1 if SHELL is a restricted shell (one not returned by
    getusershell), else 0, meaning it is a standard shell.  */
 
-int
+static int
 restricted_shell (shell)
      char *shell;
 {
   char *line;
 
   setusershell ();
-  while (line = getusershell ())
+  while ((line = getusershell ()) != NULL)
     {
       if (*line != '#' && strcmp (line, shell) == 0)
 	{
@@ -469,7 +470,7 @@ restricted_shell (shell)
 
 /* Return the number of elements in ARR, a null-terminated array.  */
 
-int
+static int
 elements (arr)
      char **arr;
 {
@@ -482,7 +483,7 @@ elements (arr)
 
 /* Add VAL to the environment, checking for out of memory errors.  */
 
-void
+static void
 xputenv (val)
      char *val;
 {
@@ -493,7 +494,7 @@ xputenv (val)
 /* Return a newly-allocated string whose contents concatenate
    those of S1, S2, S3.  */
 
-char *
+static char *
 concat (s1, s2, s3)
      char *s1, *s2, *s3;
 {
@@ -508,7 +509,7 @@ concat (s1, s2, s3)
   return result;
 }
 
-void
+static void
 usage ()
 {
   fprintf (stderr, "\
diff --git a/src/tee.c b/src/tee.c
index ca8f53a5f..b06afa8d6 100644
--- a/src/tee.c
+++ b/src/tee.c
@@ -24,10 +24,11 @@
 #include "system.h"
 
 char *xmalloc ();
-int tee ();
 void error ();
 void xwrite ();
 
+static int tee ();
+
 /* If nonzero, append to output files rather than truncating them. */
 static int append;
 
@@ -37,7 +38,7 @@ static int ignore_interrupts;
 /* The name that this program was run with. */
 char *program_name;
 
-static struct option long_options[] =
+static struct option const long_options[] =
 {
   {"append", 0, NULL, 'a'},
   {"ignore-interrupts", 0, NULL, 'i'},
@@ -101,7 +102,7 @@ Usage: %s [-ai] [--append] [--ignore-interrupts] [file...]\n",
    and into the standard output.
    Return 0 if successful, 1 if any errors occur. */
 
-int
+static int
 tee (nfiles, files)
      int nfiles;
      char **files;
diff --git a/src/test.c b/src/test.c
index a78af0968..0bc44e5dc 100644
--- a/src/test.c
+++ b/src/test.c
@@ -133,6 +133,8 @@ static int term ();
 static int and ();
 static int or ();
 
+static int group_member ();
+
 static void
 test_syntax_error (format, arg)
      char *format, *arg;
@@ -165,7 +167,6 @@ eaccess (path, mode)
      char *path;
      int mode;
 {
-  extern int group_member ();
   struct stat st;
   static int euid = -1;
 
@@ -206,7 +207,7 @@ static int default_group_array_size = 0;
 #endif /* HAVE_GETGROUPS */
 
 /* Return non-zero if GID is one that we have in our groups list. */
-int
+static int
 group_member (gid)
      gid_t gid;
 {
diff --git a/src/tty.c b/src/tty.c
index 8396aa930..7549149a9 100644
--- a/src/tty.c
+++ b/src/tty.c
@@ -26,7 +26,7 @@
 #include <sys/types.h>
 #include "system.h"
 
-void usage ();
+static void usage ();
 
 /* The name under which this program was run. */
 char *program_name;
@@ -34,7 +34,7 @@ char *program_name;
 /* If nonzero, return an exit status but produce no output. */
 static int silent;
 
-static struct option longopts[] =
+static struct option const longopts[] =
 {
   {"silent", 0, NULL, 's'},
   {"quiet", 0, NULL, 's'},
@@ -79,7 +79,7 @@ main (argc, argv)
   exit (tty == NULL);
 }
 
-void
+static void
 usage ()
 {
   fprintf (stderr, "\
diff --git a/src/uname.c b/src/uname.c
index 4b7a6f5c5..5ddd63101 100644
--- a/src/uname.c
+++ b/src/uname.c
@@ -35,8 +35,9 @@
 #include "system.h"
 
 void error ();
-void print_element ();
-void usage ();
+
+static void print_element ();
+static void usage ();
 
 /* Values that are bitwise or'd into `toprint'. */
 /* Operating system name. */
@@ -60,7 +61,7 @@ static unsigned char toprint;
 /* The name this program was run with, for error messages. */
 char *program_name;
 
-static struct option long_options[] =
+static struct option const long_options[] =
 {
   {"sysname", 0, NULL, 's'},
   {"nodename", 0, NULL, 'n'},
@@ -133,7 +134,7 @@ main (argc, argv)
    print ELEMENT; then print a space unless it is the last element to
    be printed, in which case print a newline. */
 
-void
+static void
 print_element (mask, element)
      unsigned char mask;
      char *element;
@@ -145,7 +146,7 @@ print_element (mask, element)
     }
 }
 
-void
+static void
 usage ()
 {
   fprintf (stderr, "\
diff --git a/src/who.c b/src/who.c
index 0612b6d6b..aa90c022a 100644
--- a/src/who.c
+++ b/src/who.c
@@ -56,19 +56,21 @@
 
 #define MESG_BIT 020		/* Group write bit. */
 
-char *ttyname ();
 
 char *idle_string ();
 char *xmalloc ();
-struct utmp *search_entries ();
 void error ();
-void list_entries ();
-void print_entry ();
-void print_heading ();
-void scan_entries ();
-void usage ();
-void who ();
-void who_am_i ();
+
+
+static char *ttyname ();
+static struct utmp *search_entries ();
+static void list_entries ();
+static void print_entry ();
+static void print_heading ();
+static void scan_entries ();
+static void usage ();
+static void who ();
+static void who_am_i ();
 
 /* The name this program was run with. */
 char *program_name;
@@ -90,7 +92,7 @@ static int include_heading;
    or a `?' if their tty cannot be statted. */
 static int include_mesg;
 
-static struct option longopts[] =
+static struct option const longopts[] =
 {
   {"count", 0, NULL, 'q'},
   {"idle", 0, NULL, 'u'},
@@ -180,7 +182,7 @@ static struct utmp *utmp_contents;
 
 /* Display a list of who is on the system, according to utmp file FILENAME. */
 
-void
+static void
 who (filename)
      char *filename;
 {
@@ -196,7 +198,7 @@ who (filename)
 /* Read the utmp file FILENAME into UTMP_CONTENTS and return the
    number of entries it contains. */
 
-int
+static int
 read_utmp (filename)
      char *filename;
 {
@@ -228,7 +230,7 @@ read_utmp (filename)
 
 /* Display a line of information about entry THIS. */
 
-void
+static void
 print_entry (this)
      struct utmp *this;
 {
@@ -277,7 +279,7 @@ print_entry (this)
 /* Print the username of each valid entry and the number of valid entries
    in `utmp_contents', which should have N elements. */
 
-void
+static void
 list_entries (n)
      int n;
 {
@@ -300,7 +302,7 @@ list_entries (n)
   printf ("\n# users=%u\n", entries);
 }
 
-void
+static void
 print_heading ()
 {
   struct utmp *ut;
@@ -317,7 +319,7 @@ print_heading ()
 
 /* Display `utmp_contents', which should have N entries. */
 
-void
+static void
 scan_entries (n)
      int n;
 {
@@ -343,7 +345,7 @@ scan_entries (n)
    Return the first matching entry found, or NULL if there
    is no matching entry. */
 
-struct utmp *
+static struct utmp *
 search_entries (n, line)
      int n;
      char *line;
@@ -366,7 +368,7 @@ search_entries (n, line)
 /* Display the entry in utmp file FILENAME for this tty on standard input,
    or nothing if there is no entry for it. */
 
-void
+static void
 who_am_i (filename)
      char *filename;
 {
@@ -399,7 +401,7 @@ who_am_i (filename)
 /* Return a string representing the time between WHEN and the time
    that this function is first run. */
 
-char *
+static char *
 idle_string (when)
      time_t when;
 {
@@ -423,7 +425,7 @@ idle_string (when)
   return " old ";
 }
 
-void
+static void
 usage ()
 {
   fprintf (stderr, "\