gnu/usr.bin/sort/getopt.h

   1 /* Declarations for getopt.
   2    Copyright (C) 1989, 90, 91, 92, 93, 94 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify it
   5    under the terms of the GNU General Public License as published by the
   6    Free Software Foundation; either version 2, or (at your option) any
   7    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, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  17
  18 #ifndef _GETOPT_H
  19 #define _GETOPT_H 1
  20
  21 #ifdef  __cplusplus
  22 extern "C" {
  23 #endif
  24
  25 /* For communication from `getopt' to the caller.
  26    When `getopt' finds an option that takes an argument,
  27    the argument value is returned here.
  28    Also, when `ordering' is RETURN_IN_ORDER,
  29    each non-option ARGV-element is returned here.  */
  30
  31 extern char *optarg;
  32
  33 /* Index in ARGV of the next element to be scanned.
  34    This is used for communication to and from the caller
  35    and for communication between successive calls to `getopt'.
  36
  37    On entry to `getopt', zero means this is the first call; initialize.
  38
  39    When `getopt' returns EOF, this is the index of the first of the
  40    non-option elements that the caller should itself scan.
  41
  42    Otherwise, `optind' communicates from one call to the next
  43    how much of ARGV has been scanned so far.  */
  44
  45 extern int optind;
  46
  47 /* Callers store zero here to inhibit the error message `getopt' prints
  48    for unrecognized options.  */
  49
  50 extern int opterr;
  51
  52 /* Set to an option character which was unrecognized.  */
  53
  54 extern int optopt;
  55
  56 /* Describe the long-named options requested by the application.
  57    The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
  58    of `struct option' terminated by an element containing a name which is
  59    zero.
  60
  61    The field `has_arg' is:
  62    no_argument          (or 0) if the option does not take an argument,
  63    required_argument    (or 1) if the option requires an argument,
  64    optional_argument    (or 2) if the option takes an optional argument.
  65
  66    If the field `flag' is not NULL, it points to a variable that is set
  67    to the value given in the field `val' when the option is found, but
  68    left unchanged if the option is not found.
  69
  70    To have a long-named option do something other than set an `int' to
  71    a compiled-in constant, such as set a value from `optarg', set the
  72    option's `flag' field to zero and its `val' field to a nonzero
  73    value (the equivalent single-letter option character, if there is
  74    one).  For long options that have a zero `flag' field, `getopt'
  75    returns the contents of the `val' field.  */
  76
  77 struct option
  78 {
  79 #if defined (__STDC__) && __STDC__
  80   const char *name;
  81 #else
  82   char *name;
  83 #endif
  84   /* has_arg can't be an enum because some compilers complain about
  85      type mismatches in all the code that assumes it is an int.  */
  86   int has_arg;
  87   int *flag;
  88   int val;
  89 };
  90
  91 /* Names for the values of the `has_arg' field of `struct option'.  */
  92
  93 #define no_argument             0
  94 #define required_argument       1
  95 #define optional_argument       2
  96
  97 #if defined (__STDC__) && __STDC__
  98 #ifdef __GNU_LIBRARY__
  99 /* Many other libraries have conflicting prototypes for getopt, with
 100    differences in the consts, in stdlib.h.  To avoid compilation
 101    errors, only prototype getopt for the GNU C library.  */
 102 extern int getopt (int argc, char *const *argv, const char *shortopts);
 103 #else /* not __GNU_LIBRARY__ */
 104 extern int getopt ();
 105 #endif /* __GNU_LIBRARY__ */
 106 extern int getopt_long (int argc, char *const *argv, const char *shortopts,
 107                         const struct option *longopts, int *longind);
 108 extern int getopt_long_only (int argc, char *const *argv,
 109                              const char *shortopts,
 110                              const struct option *longopts, int *longind);
 111
 112 /* Internal only.  Users should not call this directly.  */
 113 extern int _getopt_internal (int argc, char *const *argv,
 114                              const char *shortopts,
 115                              const struct option *longopts, int *longind,
 116                              int long_only);
 117 #else /* not __STDC__ */
 118 extern int getopt ();
 119 extern int getopt_long ();
 120 extern int getopt_long_only ();
 121
 122 extern int _getopt_internal ();
 123 #endif /* __STDC__ */
 124
 125 #ifdef  __cplusplus
 126 }
 127 #endif
 128
 129 #endif /* _GETOPT_H */