lib/getopt.h

   1 /* Declarations for getopt.
   2  * Copyright (C) 1989,90,91,92,93,94,96,97 Free Software Foundation, Inc.
   3  *
   4  * NOTE: The canonical source of this file is maintained with the GNU C Library.
   5  * Bugs can be reported to bug-glibc@gnu.org.
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2, or (at your option) any
  10  * later version.
  11  *
  12  * This program 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
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; see the file COPYING; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #ifndef _GETOPT_H
  23 #define _GETOPT_H 1
  24
  25 /*
  26  * The operating system may or may not provide getopt_long(), and if
  27  * so it may or may not be a version we are willing to use.  Our
  28  * strategy is to declare getopt here, and then provide code unless
  29  * the supplied version is adequate.  The difficult case is when a
  30  * declaration for getopt is provided, as our declaration must match.
  31  *
  32  * XXX Arguably this version should be named differently, and the
  33  * local names defined to refer to the system version when we choose
  34  * to use the system version.
  35  */
  36
  37 #ifdef __cplusplus
  38 extern "C" {
  39 #endif
  40
  41 /* For communication from `getopt' to the caller.
  42    When `getopt' finds an option that takes an argument,
  43    the argument value is returned here.
  44    Also, when `ordering' is RETURN_IN_ORDER,
  45    each non-option ARGV-element is returned here.  */
  46
  47 extern char *optarg;
  48
  49 /* Index in ARGV of the next element to be scanned.
  50    This is used for communication to and from the caller
  51    and for communication between successive calls to `getopt'.
  52
  53    On entry to `getopt', zero means this is the first call; initialize.
  54
  55    When `getopt' returns -1, this is the index of the first of the
  56    non-option elements that the caller should itself scan.
  57
  58    Otherwise, `optind' communicates from one call to the next
  59    how much of ARGV has been scanned so far.  */
  60
  61 extern int optind;
  62
  63 /* Callers store zero here to inhibit the error message `getopt' prints
  64    for unrecognized options.  */
  65
  66 extern int opterr;
  67
  68 /* Set to an option character which was unrecognized.  */
  69
  70 extern int optopt;
  71
  72 /* Describe the long-named options requested by the application.
  73    The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
  74    of `struct option' terminated by an element containing a name which is
  75    zero.
  76
  77    The field `has_arg' is:
  78    no_argument          (or 0) if the option does not take an argument,
  79    required_argument    (or 1) if the option requires an argument,
  80    optional_argument    (or 2) if the option takes an optional argument.
  81
  82    If the field `flag' is not NULL, it points to a variable that is set
  83    to the value given in the field `val' when the option is found, but
  84    left unchanged if the option is not found.
  85
  86    To have a long-named option do something other than set an `int' to
  87    a compiled-in constant, such as set a value from `optarg', set the
  88    option's `flag' field to zero and its `val' field to a nonzero
  89    value (the equivalent single-letter option character, if there is
  90    one).  For long options that have a zero `flag' field, `getopt'
  91    returns the contents of the `val' field.  */
  92
  93 struct option {
  94 #if defined(__STDC__) && __STDC__
  95         const char *name;
  96 #else
  97         char *name;
  98 #endif
  99         /* has_arg can't be an enum because some compilers complain about
 100            type mismatches in all the code that assumes it is an int.  */
 101         int has_arg;
 102         int *flag;
 103         int val;
 104 };
 105
 106 /* Names for the values of the `has_arg' field of `struct option'.  */
 107
 108 #define no_argument             0
 109 #define required_argument       1
 110 #define optional_argument       2
 111
 112 #if defined(__STDC__) && __STDC__
 113
 114 #if REALLY_NEED_PLAIN_GETOPT
 115
 116 /*
 117  * getopt is defined in POSIX.2.  Assume that if the system defines
 118  * getopt that it complies with POSIX.2.  If not, an autoconf test
 119  * should be written to define NONPOSIX_GETOPT_DEFINITION.
 120  */
 121 #ifndef NONPOSIX_GETOPT_DEFINITION
 122 extern int getopt(int argc, char *const *argv, const char *shortopts);
 123 #else  /* NONPOSIX_GETOPT_DEFINITION */
 124 extern int getopt(void);
 125 #endif /* NONPOSIX_GETOPT_DEFINITION */
 126
 127 #endif
 128
 129
 130 extern int getopt_long(int argc, char *const *argv, const char *shortopts,
 131                        const struct option *longopts, int *longind);
 132 extern int getopt_long_only(int argc, char *const *argv, const char *shortopts,
 133                             const struct option *longopts, int *longind);
 134
 135 /* Internal only.  Users should not call this directly.  */
 136 extern int _getopt_internal(int argc, char *const *argv, const char *shortopts,
 137                             const struct option *longopts, int *longind,
 138                             int long_only);
 139 #else /* not __STDC__ */
 140
 141 #ifdef REALLY_NEED_PLAIN_GETOPT
 142 extern int getopt();
 143 #endif /* REALLY_NEED_PLAIN_GETOPT */
 144
 145 extern int getopt_long();
 146 extern int getopt_long_only();
 147
 148 extern int _getopt_internal();
 149
 150 #endif /* __STDC__ */
 151
 152 #ifdef __cplusplus
 153 }
 154 #endif
 155
 156 #endif /* getopt.h */