posix/getopt.h

   1 /* Declarations for getopt.
   2    Copyright (C) 1989,90,91,92,93,94,96,97 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 #ifndef _GETOPT_H
  21 #define _GETOPT_H 1
  22
  23 #ifdef  __cplusplus
  24 extern "C" {
  25 #endif
  26
  27 /* For communication from `getopt' to the caller.
  28    When `getopt' finds an option that takes an argument,
  29    the argument value is returned here.
  30    Also, when `ordering' is RETURN_IN_ORDER,
  31    each non-option ARGV-element is returned here.  */
  32
  33 extern char *optarg;
  34
  35 /* Index in ARGV of the next element to be scanned.
  36    This is used for communication to and from the caller
  37    and for communication between successive calls to `getopt'.
  38
  39    On entry to `getopt', zero means this is the first call; initialize.
  40
  41    When `getopt' returns -1, this is the index of the first of the
  42    non-option elements that the caller should itself scan.
  43
  44    Otherwise, `optind' communicates from one call to the next
  45    how much of ARGV has been scanned so far.  */
  46
  47 extern int optind;
  48
  49 /* Callers store zero here to inhibit the error message `getopt' prints
  50    for unrecognized options.  */
  51
  52 extern int opterr;
  53
  54 /* Set to an option character which was unrecognized.  */
  55
  56 extern int optopt;
  57
  58 /* Describe the long-named options requested by the application.
  59    The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
  60    of `struct option' terminated by an element containing a name which is
  61    zero.
  62
  63    The field `has_arg' is:
  64    no_argument          (or 0) if the option does not take an argument,
  65    required_argument    (or 1) if the option requires an argument,
  66    optional_argument    (or 2) if the option takes an optional argument.
  67
  68    If the field `flag' is not NULL, it points to a variable that is set
  69    to the value given in the field `val' when the option is found, but
  70    left unchanged if the option is not found.
  71
  72    To have a long-named option do something other than set an `int' to
  73    a compiled-in constant, such as set a value from `optarg', set the
  74    option's `flag' field to zero and its `val' field to a nonzero
  75    value (the equivalent single-letter option character, if there is
  76    one).  For long options that have a zero `flag' field, `getopt'
  77    returns the contents of the `val' field.  */
  78
  79 struct option
  80 {
  81 #if defined (__STDC__) && __STDC__
  82   const char *name;
  83 #else
  84   char *name;
  85 #endif
  86   /* has_arg can't be an enum because some compilers complain about
  87      type mismatches in all the code that assumes it is an int.  */
  88   int has_arg;
  89   int *flag;
  90   int val;
  91 };
  92
  93 /* Names for the values of the `has_arg' field of `struct option'.  */
  94
  95 #define no_argument             0
  96 #define required_argument       1
  97 #define optional_argument       2
  98
  99 #if defined (__STDC__) && __STDC__
 100 #ifdef __GNU_LIBRARY__
 101 /* Many other libraries have conflicting prototypes for getopt, with
 102    differences in the consts, in stdlib.h.  To avoid compilation
 103    errors, only prototype getopt for the GNU C library.  */
 104 extern int getopt (int argc, char *const *argv, const char *shortopts);
 105 #else /* not __GNU_LIBRARY__ */
 106 extern int getopt ();
 107 #endif /* __GNU_LIBRARY__ */
 108 extern int getopt_long (int argc, char *const *argv, const char *shortopts,
 109                         const struct option *longopts, int *longind);
 110 extern int getopt_long_only (int argc, char *const *argv,
 111                              const char *shortopts,
 112                              const struct option *longopts, int *longind);
 113
 114 /* Internal only.  Users should not call this directly.  */
 115 extern int _getopt_internal (int argc, char *const *argv,
 116                              const char *shortopts,
 117                              const struct option *longopts, int *longind,
 118                              int long_only);
 119 #else /* not __STDC__ */
 120 extern int getopt ();
 121 extern int getopt_long ();
 122 extern int getopt_long_only ();
 123
 124 extern int _getopt_internal ();
 125 #endif /* __STDC__ */
 126
 127 #ifdef  __cplusplus
 128 }
 129 #endif
 130
 131 #endif /* getopt.h */