finch/getopt.h
1 /* Declarations for getopt.
2 
3  NOTE: getopt is now part of the C library, so if you don't know what
4  "Keep this file name-space clean" means, talk to roland@gnu.ai.mit.edu
5  before changing it!
6 
7  Finch is the legal property of its developers, whose names are too numerous
8  to list here. Please refer to the COPYRIGHT file distributed with this
9  source distribution.
10 
11  This program is free software; you can redistribute it and/or modify it
12  under the terms of the GNU General Public License as published by the
13  Free Software Foundation; either version 2, or (at your option) any
14  later version.
15 
16  This program is distributed in the hope that it will be useful,
17  but WITHOUT ANY WARRANTY; without even the implied warranty of
18  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  GNU General Public License for more details.
20 
21  You should have received a copy of the GNU General Public License
22  along with this program; if not, write to the Free Software
23  Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
24 
25 #ifndef _GETOPT_H
26 #define _GETOPT_H 1
27 
28 #ifdef __cplusplus
29 extern "C" {
30 #endif
31 
32 /* For communication from `getopt' to the caller.
33  When `getopt' finds an option that takes an argument,
34  the argument value is returned here.
35  Also, when `ordering' is RETURN_IN_ORDER,
36  each non-option ARGV-element is returned here. */
37 
38 extern char *optarg;
39 
40 /* Index in ARGV of the next element to be scanned.
41  This is used for communication to and from the caller
42  and for communication between successive calls to `getopt'.
43 
44  On entry to `getopt', zero means this is the first call; initialize.
45 
46  When `getopt' returns EOF, this is the index of the first of the
47  non-option elements that the caller should itself scan.
48 
49  Otherwise, `optind' communicates from one call to the next
50  how much of ARGV has been scanned so far. */
51 
52 extern int optind;
53 
54 /* Callers store zero here to inhibit the error message `getopt' prints
55  for unrecognized options. */
56 
57 extern int opterr;
58 
59 /* Set to an option character which was unrecognized. */
60 
61 extern int optopt;
62 
63 /* Describe the long-named options requested by the application.
64  The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
65  of `struct option' terminated by an element containing a name which is
66  zero.
67 
68  The field `has_arg' is:
69  no_argument (or 0) if the option does not take an argument,
70  required_argument (or 1) if the option requires an argument,
71  optional_argument (or 2) if the option takes an optional argument.
72 
73  If the field `flag' is not NULL, it points to a variable that is set
74  to the value given in the field `val' when the option is found, but
75  left unchanged if the option is not found.
76 
77  To have a long-named option do something other than set an `int' to
78  a compiled-in constant, such as set a value from `optarg', set the
79  option's `flag' field to zero and its `val' field to a nonzero
80  value (the equivalent single-letter option character, if there is
81  one). For long options that have a zero `flag' field, `getopt'
82  returns the contents of the `val' field. */
83 
84 struct option
85 {
86 #if __STDC__
87  const char *name;
88 #else
89  char *name;
90 #endif
91  /* has_arg can't be an enum because some compilers complain about
92  type mismatches in all the code that assumes it is an int. */
93  int has_arg;
94  int *flag;
95  int val;
96 };
97 
98 /* Names for the values of the `has_arg' field of `struct option'. */
99 
100 #define no_argument 0
101 #define required_argument 1
102 #define optional_argument 2
103 
104 #if __STDC__
105 #if defined(__GNU_LIBRARY__)
106 /* Many other libraries have conflicting prototypes for getopt, with
107  differences in the consts, in stdlib.h. To avoid compilation
108  errors, only prototype getopt for the GNU C library. */
109 extern int getopt (int argc, char *const *argv, const char *shortopts);
110 #else /* not __GNU_LIBRARY__ */
111 extern int getopt ();
112 #endif /* not __GNU_LIBRARY__ */
113 extern int getopt_long (int argc, char *const *argv, const char *shortopts,
114  const struct option *longopts, int *longind);
115 extern int getopt_long_only (int argc, char *const *argv,
116  const char *shortopts,
117  const struct option *longopts, int *longind);
118 
119 /* Internal only. Users should not call this directly. */
120 extern int _getopt_internal (int argc, char *const *argv,
121  const char *shortopts,
122  const struct option *longopts, int *longind,
123  int long_only);
124 #else /* not __STDC__ */
125 extern int getopt ();
126 extern int getopt_long ();
127 extern int getopt_long_only ();
128 
129 extern int _getopt_internal ();
130 #endif /* not __STDC__ */
131 
132 #ifdef __cplusplus
133 }
134 #endif
135 
136 #endif /* _GETOPT_H */