L4Re Operating System Framework
Interface and Usage Documentation
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getopt.h
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1
5/*
6 * (c) 2008-2009 Adam Lackorzynski <adam@os.inf.tu-dresden.de>,
7 * Alexander Warg <warg@os.inf.tu-dresden.de>
8 * economic rights: Technische Universität Dresden (Germany)
9 * This file is part of TUD:OS and distributed under the terms of the
10 * GNU Lesser General Public License 2.1.
11 * Please see the COPYING-LGPL-2.1 file for details.
12 */
13#ifndef _GETOPT_H
14#define _GETOPT_H
15
16#ifndef NULL
17#define NULL 0
18#endif
19
20#include <l4/sys/compiler.h>
21
23
24/* For communication from `getopt' to the caller.
25 When `getopt' finds an option that takes an argument,
26 the argument value is returned here.
27 Also, when `ordering' is RETURN_IN_ORDER,
28 each non-option ARGV-element is returned here. */
29
30extern char *optarg;
31
32/* Index in ARGV of the next element to be scanned.
33 This is used for communication to and from the caller
34 and for communication between successive calls to `getopt'.
35
36 On entry to `getopt', zero means this is the first call; initialize.
37
38 When `getopt' returns -1, this is the index of the first of the
39 non-option elements that the caller should itself scan.
40
41 Otherwise, `optind' communicates from one call to the next
42 how much of ARGV has been scanned so far. */
43
44extern int optind;
45
46/* Callers store zero here to inhibit the error message `getopt' prints
47 for unrecognized options. */
48
49extern int opterr;
50
51/* Set to an option character which was unrecognized. */
52
53extern int optopt;
54
55/* Describe the long-named options requested by the application.
56 The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
57 of `struct option' terminated by an element containing a name which is
58 zero.
59
60 The field `has_arg' is:
61 no_argument (or 0) if the option does not take an argument,
62 required_argument (or 1) if the option requires an argument,
63 optional_argument (or 2) if the option takes an optional argument.
64
65 If the field `flag' is not NULL, it points to a variable that is set
66 to the value given in the field `val' when the option is found, but
67 left unchanged if the option is not found.
68
69 To have a long-named option do something other than set an `int' to
70 a compiled-in constant, such as set a value from `optarg', set the
71 option's `flag' field to zero and its `val' field to a nonzero
72 value (the equivalent single-letter option character, if there is
73 one). For long options that have a zero `flag' field, `getopt'
74 returns the contents of the `val' field. */
75
76struct option
77{
78 const char *name;
79 /* has_arg can't be an enum because some compilers complain about
80 type mismatches in all the code that assumes it is an int. */
81 int has_arg;
82 int *flag;
83 int val;
84};
85
86/* Names for the values of the `has_arg' field of `struct option'. */
87
88#define no_argument 0
89#define required_argument 1
90#define optional_argument 2
91
92L4_CV int getopt (int argc, char *const *argv, const char *shortopts);
93
94L4_CV int getopt_long (int argc, char *const *argv, const char *shortopts,
95 const struct option *longopts, int *longind);
96L4_CV int getopt_long_only (int argc, char *const *argv,
97 const char *shortopts,
98 const struct option *longopts, int *longind);
99
100L4_CV int _getopt_internal (int argc, char *const *argv,
101 const char *shortopts,
102 const struct option *longopts, int *longind,
103 int long_only);
104
106
107#endif /* _GETOPT_H */
L4 compiler related defines.
#define L4_CV
Define calling convention.
Definition linkage.h:44
#define EXTERN_C_BEGIN
Start section with C types and functions.
Definition compiler.h:192
#define EXTERN_C_END
End section with C types and functions.
Definition compiler.h:193