include/getopt.h

   1 /* Declarations for getopt.
   2    Copyright (C) 1989, 1990, 1991, 1992 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software
  16    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  17
  18 #ifndef _GETOPT_H
  19 #define _GETOPT_H 1
  20
  21 /* For communication from `getopt' to the caller.
  22    When `getopt' finds an option that takes an argument,
  23    the argument value is returned here.
  24    Also, when `ordering' is RETURN_IN_ORDER,
  25    each non-option ARGV-element is returned here.  */
  26
  27 extern char *optarg;
  28
  29 /* Index in ARGV of the next element to be scanned.
  30    This is used for communication to and from the caller
  31    and for communication between successive calls to `getopt'.
  32
  33    On entry to `getopt', zero means this is the first call; initialize.
  34
  35    When `getopt' returns EOF, this is the index of the first of the
  36    non-option elements that the caller should itself scan.
  37
  38    Otherwise, `optind' communicates from one call to the next
  39    how much of ARGV has been scanned so far.  */
  40
  41 extern int optind;
  42
  43 /* Callers store zero here to inhibit the error message `getopt' prints
  44    for unrecognized options.  */
  45
  46 extern int opterr;
  47
  48 /* Describe the long-named options requested by the application.
  49    The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
  50    of `struct option' terminated by an element containing a name which is
  51    zero.
  52
  53    The field `has_arg' is:
  54    no_argument          (or 0) if the option does not take an argument,
  55    required_argument    (or 1) if the option requires an argument,
  56    optional_argument    (or 2) if the option takes an optional argument.
  57
  58    If the field `flag' is not NULL, it points to a variable that is set
  59    to the value given in the field `val' when the option is found, but
  60    left unchanged if the option is not found.
  61
  62    To have a long-named option do something other than set an `int' to
  63    a compiled-in constant, such as set a value from `optarg', set the
  64    option's `flag' field to zero and its `val' field to a nonzero
  65    value (the equivalent single-letter option character, if there is
  66    one).  For long options that have a zero `flag' field, `getopt'
  67    returns the contents of the `val' field.  */
  68
  69 struct option
  70 {
  71 #if     __STDC__
  72   const char *name;
  73 #else
  74   char *name;
  75 #endif
  76   /* has_arg can't be an enum because some compilers complain about
  77      type mismatches in all the code that assumes it is an int.  */
  78   int has_arg;
  79   int *flag;
  80   int val;
  81 };
  82
  83 /* Names for the values of the `has_arg' field of `struct option'.  */
  84
  85 enum _argtype
  86 {
  87   no_argument,
  88   required_argument,
  89   optional_argument
  90 };
  91
  92 #if __STDC__
  93 extern int getopt (int argc, char *const *argv, const char *shortopts);
  94 extern int getopt_long (int argc, char *const *argv, const char *shortopts,
  95                         const struct option *longopts, int *longind);
  96 extern int getopt_long_only (int argc, char *const *argv,
  97                              const char *shortopts,
  98                              const struct option *longopts, int *longind);
  99
 100 /* Internal only.  Users should not call this directly.  */
 101 extern int _getopt_internal (int argc, char *const *argv,
 102                              const char *shortopts,
 103                              const struct option *longopts, int *longind,
 104                              int long_only);
 105 #else /* not __STDC__ */
 106 extern int getopt ();
 107 extern int getopt_long ();
 108 extern int getopt_long_only ();
 109
 110 extern int _getopt_internal ();
 111 #endif /* not __STDC__ */
 112
 113 #endif /* _GETOPT_H */