include/getopt.h

   1 /* Declarations for getopt.
   2    Copyright 1989, 1990, 1991, 1992, 1993, 1994, 1996, 1997, 1998, 2000,
   3    2002 Free Software Foundation, Inc.
   4
   5    NOTE: The canonical source of this file is maintained with the GNU C Library.
   6    Bugs can be reported to bug-glibc@gnu.org.
   7
   8    This program is free software; you can redistribute it and/or modify it
   9    under the terms of the GNU General Public License as published by the
  10    Free Software Foundation; either version 2, or (at your option) any
  11    later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301,
  21    USA.  */
  22
  23 #ifndef _GETOPT_H
  24 #define _GETOPT_H 1
  25
  26 #ifdef  __cplusplus
  27 extern "C" {
  28 #endif
  29
  30 /* For communication from `getopt' to the caller.
  31    When `getopt' finds an option that takes an argument,
  32    the argument value is returned here.
  33    Also, when `ordering' is RETURN_IN_ORDER,
  34    each non-option ARGV-element is returned here.  */
  35
  36 extern char *optarg;
  37
  38 /* Index in ARGV of the next element to be scanned.
  39    This is used for communication to and from the caller
  40    and for communication between successive calls to `getopt'.
  41
  42    On entry to `getopt', zero means this is the first call; initialize.
  43
  44    When `getopt' returns -1, this is the index of the first of the
  45    non-option elements that the caller should itself scan.
  46
  47    Otherwise, `optind' communicates from one call to the next
  48    how much of ARGV has been scanned so far.  */
  49
  50 extern int optind;
  51
  52 /* Callers store zero here to inhibit the error message `getopt' prints
  53    for unrecognized options.  */
  54
  55 extern int opterr;
  56
  57 /* Set to an option character which was unrecognized.  */
  58
  59 extern int optopt;
  60
  61 /* Describe the long-named options requested by the application.
  62    The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
  63    of `struct option' terminated by an element containing a name which is
  64    zero.
  65
  66    The field `has_arg' is:
  67    no_argument          (or 0) if the option does not take an argument,
  68    required_argument    (or 1) if the option requires an argument,
  69    optional_argument    (or 2) if the option takes an optional argument.
  70
  71    If the field `flag' is not NULL, it points to a variable that is set
  72    to the value given in the field `val' when the option is found, but
  73    left unchanged if the option is not found.
  74
  75    To have a long-named option do something other than set an `int' to
  76    a compiled-in constant, such as set a value from `optarg', set the
  77    option's `flag' field to zero and its `val' field to a nonzero
  78    value (the equivalent single-letter option character, if there is
  79    one).  For long options that have a zero `flag' field, `getopt'
  80    returns the contents of the `val' field.  */
  81
  82 struct option
  83 {
  84 #if defined (__STDC__) && __STDC__
  85   const char *name;
  86 #else
  87   char *name;
  88 #endif
  89   /* has_arg can't be an enum because some compilers complain about
  90      type mismatches in all the code that assumes it is an int.  */
  91   int has_arg;
  92   int *flag;
  93   int val;
  94 };
  95
  96 /* Names for the values of the `has_arg' field of `struct option'.  */
  97
  98 #define no_argument             0
  99 #define required_argument       1
 100 #define optional_argument       2
 101
 102 #if defined (__STDC__) && __STDC__
 103 /* HAVE_DECL_* is a three-state macro: undefined, 0 or 1.  If it is
 104    undefined, we haven't run the autoconf check so provide the
 105    declaration without arguments.  If it is 0, we checked and failed
 106    to find the declaration so provide a fully prototyped one.  If it
 107    is 1, we found it so don't provide any declaration at all.  */
 108 #if !HAVE_DECL_GETOPT
 109 #if defined (__GNU_LIBRARY__) || defined (HAVE_DECL_GETOPT)
 110 /* Many other libraries have conflicting prototypes for getopt, with
 111    differences in the consts, in unistd.h.  To avoid compilation
 112    errors, only prototype getopt for the GNU C library.  */
 113 extern int getopt (int argc, char *const *argv, const char *shortopts);
 114 #else
 115 #ifndef __cplusplus
 116 extern int getopt ();
 117 #endif /* __cplusplus */
 118 #endif
 119 #endif /* !HAVE_DECL_GETOPT */
 120
 121 extern int getopt_long (int argc, char *const *argv, const char *shortopts,
 122                         const struct option *longopts, int *longind);
 123 extern int getopt_long_only (int argc, char *const *argv,
 124                              const char *shortopts,
 125                              const struct option *longopts, int *longind);
 126
 127 /* Internal only.  Users should not call this directly.  */
 128 extern int _getopt_internal (int argc, char *const *argv,
 129                              const char *shortopts,
 130                              const struct option *longopts, int *longind,
 131                              int long_only);
 132 #else /* not __STDC__ */
 133 extern int getopt ();
 134 extern int getopt_long ();
 135 extern int getopt_long_only ();
 136
 137 extern int _getopt_internal ();
 138 #endif /* __STDC__ */
 139
 140 #ifdef  __cplusplus
 141 }
 142 #endif
 143
 144 #endif /* getopt.h */