1 /* Declarations for getopt (basic, portable features only).
2 Copyright (C) 1989-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library and is also part of gnulib.
4 Patches to this file should be submitted to both projects.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <https://www.gnu.org/licenses/>. */
19
20 #ifndef _GETOPT_CORE_H
21 #define _GETOPT_CORE_H 1
22
23 /* This header should not be used directly; include getopt.h or
24 unistd.h instead. Unlike most bits headers, it does not have
25 a protective #error, because the guard macro for getopt.h in
26 gnulib is not fixed. */
27
28 __BEGIN_DECLS
29
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. */
35
36 extern char *optarg;
37
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'.
41
42 On entry to 'getopt', zero means this is the first call; initialize.
43
44 When 'getopt' returns -1, this is the index of the first of the
45 non-option elements that the caller should itself scan.
46
47 Otherwise, 'optind' communicates from one call to the next
48 how much of ARGV has been scanned so far. */
49
50 extern int optind;
51
52 /* Callers store zero here to inhibit the error message 'getopt' prints
53 for unrecognized options. */
54
55 extern int opterr;
56
57 /* Set to an option character which was unrecognized. */
58
59 extern int optopt;
60
61 /* Get definitions and prototypes for functions to process the
62 arguments in ARGV (ARGC of them, minus the program name) for
63 options given in OPTS.
64
65 Return the option character from OPTS just read. Return -1 when
66 there are no more options. For unrecognized options, or options
67 missing arguments, 'optopt' is set to the option letter, and '?' is
68 returned.
69
70 The OPTS string is a list of characters which are recognized option
71 letters, optionally followed by colons, specifying that that letter
72 takes an argument, to be placed in 'optarg'.
73
74 If a letter in OPTS is followed by two colons, its argument is
75 optional. This behavior is specific to the GNU 'getopt'.
76
77 The argument '--' causes premature termination of argument
78 scanning, explicitly telling 'getopt' that there are no more
79 options.
80
81 If OPTS begins with '-', then non-option arguments are treated as
82 arguments to the option '\1'. This behavior is specific to the GNU
83 'getopt'. If OPTS begins with '+', or POSIXLY_CORRECT is set in
84 the environment, then do not permute arguments.
85
86 For standards compliance, the 'argv' argument has the type
87 char *const *, but this is inaccurate; if argument permutation is
88 enabled, the argv array (not the strings it points to) must be
89 writable. */
90
91 extern int getopt (int ___argc, char *const *___argv, const char *__shortopts)
92 __THROW _GL_ARG_NONNULL ((2, 3));
93
94 __END_DECLS
95
96 #endif /* _GETOPT_CORE_H */