posix/getopt.h

   1 /* Declarations for getopt.
   2    Copyright (C) 1989, 90, 91, 92, 93, 94 Free Software Foundation, Inc.
   3
   4 This file is part of the GNU C Library.  Its master source is NOT part of
   5 the C library, however.  The master source lives in /gd/gnu/lib.
   6
   7 The GNU C Library is free software; you can redistribute it and/or
   8 modify it under the terms of the GNU Library General Public License as
   9 published by the Free Software Foundation; either version 2 of the
  10 License, or (at your option) any later version.
  11
  12 The GNU C Library is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 Library General Public License for more details.
  16
  17 You should have received a copy of the GNU Library General Public
  18 License along with the GNU C Library; see the file COPYING.LIB.  If
  19 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  20 Cambridge, MA 02139, USA.  */
  21
  22 #ifndef _GETOPT_H
  23 #define _GETOPT_H 1
  24
  25 #ifdef  __cplusplus
  26 extern "C" {
  27 #endif
  28
  29 /* For communication from `getopt' to the caller.
  30    When `getopt' finds an option that takes an argument,
  31    the argument value is returned here.
  32    Also, when `ordering' is RETURN_IN_ORDER,
  33    each non-option ARGV-element is returned here.  */
  34
  35 extern char *optarg;
  36
  37 /* Index in ARGV of the next element to be scanned.
  38    This is used for communication to and from the caller
  39    and for communication between successive calls to `getopt'.
  40
  41    On entry to `getopt', zero means this is the first call; initialize.
  42
  43    When `getopt' returns EOF, this is the index of the first of the
  44    non-option elements that the caller should itself scan.
  45
  46    Otherwise, `optind' communicates from one call to the next
  47    how much of ARGV has been scanned so far.  */
  48
  49 extern int optind;
  50
  51 /* Callers store zero here to inhibit the error message `getopt' prints
  52    for unrecognized options.  */
  53
  54 extern int opterr;
  55
  56 /* Set to an option character which was unrecognized.  */
  57
  58 extern int optopt;
  59
  60 /* Describe the long-named options requested by the application.
  61    The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
  62    of `struct option' terminated by an element containing a name which is
  63    zero.
  64
  65    The field `has_arg' is:
  66    no_argument          (or 0) if the option does not take an argument,
  67    required_argument    (or 1) if the option requires an argument,
  68    optional_argument    (or 2) if the option takes an optional argument.
  69
  70    If the field `flag' is not NULL, it points to a variable that is set
  71    to the value given in the field `val' when the option is found, but
  72    left unchanged if the option is not found.
  73
  74    To have a long-named option do something other than set an `int' to
  75    a compiled-in constant, such as set a value from `optarg', set the
  76    option's `flag' field to zero and its `val' field to a nonzero
  77    value (the equivalent single-letter option character, if there is
  78    one).  For long options that have a zero `flag' field, `getopt'
  79    returns the contents of the `val' field.  */
  80
  81 struct option
  82 {
  83 #if defined (__STDC__) && __STDC__
  84   const char *name;
  85 #else
  86   char *name;
  87 #endif
  88   /* has_arg can't be an enum because some compilers complain about
  89      type mismatches in all the code that assumes it is an int.  */
  90   int has_arg;
  91   int *flag;
  92   int val;
  93 };
  94
  95 /* Names for the values of the `has_arg' field of `struct option'.  */
  96
  97 #define no_argument             0
  98 #define required_argument       1
  99 #define optional_argument       2
 100
 101 #if defined (__STDC__) && __STDC__
 102 #ifdef __GNU_LIBRARY__
 103 /* Many other libraries have conflicting prototypes for getopt, with
 104    differences in the consts, in stdlib.h.  To avoid compilation
 105    errors, only prototype getopt for the GNU C library.  */
 106 extern int getopt (int argc, char *const *argv, const char *shortopts);
 107 #else /* not __GNU_LIBRARY__ */
 108 extern int getopt ();
 109 #endif /* __GNU_LIBRARY__ */
 110 extern int getopt_long (int argc, char *const *argv, const char *shortopts,
 111                         const struct option *longopts, int *longind);
 112 extern int getopt_long_only (int argc, char *const *argv,
 113                              const char *shortopts,
 114                              const struct option *longopts, int *longind);
 115
 116 /* Internal only.  Users should not call this directly.  */
 117 extern int _getopt_internal (int argc, char *const *argv,
 118                              const char *shortopts,
 119                              const struct option *longopts, int *longind,
 120                              int long_only);
 121 #else /* not __STDC__ */
 122 extern int getopt ();
 123 extern int getopt_long ();
 124 extern int getopt_long_only ();
 125
 126 extern int _getopt_internal ();
 127 #endif /* __STDC__ */
 128
 129 #ifdef  __cplusplus
 130 }
 131 #endif
 132
 133 #endif /* _GETOPT_H */