2001-02-24 Michael Kifer <kifer@cs.sunysb.edu>
[emacs.git] / lib-src / getopt.h
blobba24c14ba4455e8468e4ac53f72d0f31aeaeed02
1 /* Declarations for getopt.
2 Copyright (C) 1989,90,91,92,93,94,96,97,98 Free Software Foundation, Inc.
3 NOTE: The canonical source of this file is maintained with the GNU C Library.
4 Bugs can be reported to bug-glibc@gnu.org.
5 This program is free software; you can redistribute it and/or modify it
6 under the terms of the GNU General Public License as published by the
7 Free Software Foundation; either version 2, or (at your option) any
8 later version.
10 This program 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
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
18 USA. */
20 #ifndef _GETOPT_H
22 #ifndef __need_getopt
23 # define _GETOPT_H 1
24 #endif
26 #ifdef __cplusplus
27 extern "C" {
28 #endif
30 /* For communication from `getopt' to the caller.
31 When `getopt' finds an option that takes an argument,
32 the argument value is returned here.
33 Also, when `ordering' is RETURN_IN_ORDER,
34 each non-option ARGV-element is returned here. */
36 extern char *optarg;
38 /* Index in ARGV of the next element to be scanned.
39 This is used for communication to and from the caller
40 and for communication between successive calls to `getopt'.
42 On entry to `getopt', zero means this is the first call; initialize.
44 When `getopt' returns -1, this is the index of the first of the
45 non-option elements that the caller should itself scan.
47 Otherwise, `optind' communicates from one call to the next
48 how much of ARGV has been scanned so far. */
50 extern int optind;
52 /* Callers store zero here to inhibit the error message `getopt' prints
53 for unrecognized options. */
55 extern int opterr;
57 /* Set to an option character which was unrecognized. */
59 extern int optopt;
61 #ifndef __need_getopt
62 /* Describe the long-named options requested by the application.
63 The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
64 of `struct option' terminated by an element containing a name which is
65 zero.
67 The field `has_arg' is:
68 no_argument (or 0) if the option does not take an argument,
69 required_argument (or 1) if the option requires an argument,
70 optional_argument (or 2) if the option takes an optional argument.
72 If the field `flag' is not NULL, it points to a variable that is set
73 to the value given in the field `val' when the option is found, but
74 left unchanged if the option is not found.
76 To have a long-named option do something other than set an `int' to
77 a compiled-in constant, such as set a value from `optarg', set the
78 option's `flag' field to zero and its `val' field to a nonzero
79 value (the equivalent single-letter option character, if there is
80 one). For long options that have a zero `flag' field, `getopt'
81 returns the contents of the `val' field. */
83 struct option
85 # if defined __STDC__ && __STDC__
86 const char *name;
87 # else
88 char *name;
89 # endif
90 /* has_arg can't be an enum because some compilers complain about
91 type mismatches in all the code that assumes it is an int. */
92 int has_arg;
93 int *flag;
94 int val;
97 /* Names for the values of the `has_arg' field of `struct option'. */
99 # define no_argument 0
100 # define required_argument 1
101 # define optional_argument 2
102 #endif /* need getopt */
105 /* Get definitions and prototypes for functions to process the
106 arguments in ARGV (ARGC of them, minus the program name) for
107 options given in OPTS.
109 Return the option character from OPTS just read. Return -1 when
110 there are no more options. For unrecognized options, or options
111 missing arguments, `optopt' is set to the option letter, and '?' is
112 returned.
114 The OPTS string is a list of characters which are recognized option
115 letters, optionally followed by colons, specifying that that letter
116 takes an argument, to be placed in `optarg'.
118 If a letter in OPTS is followed by two colons, its argument is
119 optional. This behavior is specific to the GNU `getopt'.
121 The argument `--' causes premature termination of argument
122 scanning, explicitly telling `getopt' that there are no more
123 options.
125 If OPTS begins with `--', then non-option arguments are treated as
126 arguments to the option '\0'. This behavior is specific to the GNU
127 `getopt'. */
129 #if defined __STDC__ && __STDC__
130 # ifdef __GNU_LIBRARY__
131 /* Many other libraries have conflicting prototypes for getopt, with
132 differences in the consts, in stdlib.h. To avoid compilation
133 errors, only prototype getopt for the GNU C library. */
134 extern int getopt (int __argc, char *const *__argv, const char *__shortopts);
135 # else /* not __GNU_LIBRARY__ */
136 extern int getopt ();
137 # endif /* __GNU_LIBRARY__ */
139 # ifndef __need_getopt
140 extern int getopt_long (int argc, char *const *argv, const char *__shortopts,
141 const struct option *__longopts, int *__longind);
142 extern int getopt_long_only (int argc, char *const *argv,
143 const char *__shortopts,
144 const struct option *__longopts, int *__longind);
146 /* Internal only. Users should not call this directly. */
147 extern int _getopt_internal (int argc, char *const *argv,
148 const char *__shortopts,
149 const struct option *__longopts, int *__longind,
150 int __long_only);
151 # endif
152 #else /* not __STDC__ */
153 extern int getopt ();
154 # ifndef __need_getopt
155 extern int getopt_long ();
156 extern int getopt_long_only ();
158 extern int _getopt_internal ();
159 # endif
160 #endif /* __STDC__ */
162 #ifdef __cplusplus
164 #endif
166 /* Make sure we later can get all the definitions and declarations. */
167 #undef __need_getopt
169 #endif /* getopt.h */