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glibc  2.9
getopt.h
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00001 /* Declarations for getopt.
00002    Copyright (C) 1989-1994,1996-1999,2001,2003,2004
00003    Free Software Foundation, Inc.
00004    This file is part of the GNU C Library.
00005 
00006    The GNU C Library is free software; you can redistribute it and/or
00007    modify it under the terms of the GNU Lesser General Public
00008    License as published by the Free Software Foundation; either
00009    version 2.1 of the License, or (at your option) any later version.
00010 
00011    The GNU C Library is distributed in the hope that it will be useful,
00012    but WITHOUT ANY WARRANTY; without even the implied warranty of
00013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014    Lesser General Public License for more details.
00015 
00016    You should have received a copy of the GNU Lesser General Public
00017    License along with the GNU C Library; if not, write to the Free
00018    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00019    02111-1307 USA.  */
00020 
00021 #ifndef _GETOPT_H
00022 
00023 #ifndef __need_getopt
00024 # define _GETOPT_H 1
00025 #endif
00026 
00027 /* If __GNU_LIBRARY__ is not already defined, either we are being used
00028    standalone, or this is the first header included in the source file.
00029    If we are being used with glibc, we need to include <features.h>, but
00030    that does not exist if we are standalone.  So: if __GNU_LIBRARY__ is
00031    not defined, include <ctype.h>, which will pull in <features.h> for us
00032    if it's from glibc.  (Why ctype.h?  It's guaranteed to exist and it
00033    doesn't flood the namespace with stuff the way some other headers do.)  */
00034 #if !defined __GNU_LIBRARY__
00035 # include <ctype.h>
00036 #endif
00037 
00038 #ifndef __THROW
00039 # ifndef __GNUC_PREREQ
00040 #  define __GNUC_PREREQ(maj, min) (0)
00041 # endif
00042 # if defined __cplusplus && __GNUC_PREREQ (2,8)
00043 #  define __THROW    throw ()
00044 # else
00045 #  define __THROW
00046 # endif
00047 #endif
00048 
00049 #ifdef __cplusplus
00050 extern "C" {
00051 #endif
00052 
00053 /* For communication from `getopt' to the caller.
00054    When `getopt' finds an option that takes an argument,
00055    the argument value is returned here.
00056    Also, when `ordering' is RETURN_IN_ORDER,
00057    each non-option ARGV-element is returned here.  */
00058 
00059 extern char *optarg;
00060 
00061 /* Index in ARGV of the next element to be scanned.
00062    This is used for communication to and from the caller
00063    and for communication between successive calls to `getopt'.
00064 
00065    On entry to `getopt', zero means this is the first call; initialize.
00066 
00067    When `getopt' returns -1, this is the index of the first of the
00068    non-option elements that the caller should itself scan.
00069 
00070    Otherwise, `optind' communicates from one call to the next
00071    how much of ARGV has been scanned so far.  */
00072 
00073 extern int optind;
00074 
00075 /* Callers store zero here to inhibit the error message `getopt' prints
00076    for unrecognized options.  */
00077 
00078 extern int opterr;
00079 
00080 /* Set to an option character which was unrecognized.  */
00081 
00082 extern int optopt;
00083 
00084 #ifndef __need_getopt
00085 /* Describe the long-named options requested by the application.
00086    The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
00087    of `struct option' terminated by an element containing a name which is
00088    zero.
00089 
00090    The field `has_arg' is:
00091    no_argument              (or 0) if the option does not take an argument,
00092    required_argument (or 1) if the option requires an argument,
00093    optional_argument        (or 2) if the option takes an optional argument.
00094 
00095    If the field `flag' is not NULL, it points to a variable that is set
00096    to the value given in the field `val' when the option is found, but
00097    left unchanged if the option is not found.
00098 
00099    To have a long-named option do something other than set an `int' to
00100    a compiled-in constant, such as set a value from `optarg', set the
00101    option's `flag' field to zero and its `val' field to a nonzero
00102    value (the equivalent single-letter option character, if there is
00103    one).  For long options that have a zero `flag' field, `getopt'
00104    returns the contents of the `val' field.  */
00105 
00106 struct option
00107 {
00108   const char *name;
00109   /* has_arg can't be an enum because some compilers complain about
00110      type mismatches in all the code that assumes it is an int.  */
00111   int has_arg;
00112   int *flag;
00113   int val;
00114 };
00115 
00116 /* Names for the values of the `has_arg' field of `struct option'.  */
00117 
00118 # define no_argument        0
00119 # define required_argument  1
00120 # define optional_argument  2
00121 #endif /* need getopt */
00122 
00123 
00124 /* Get definitions and prototypes for functions to process the
00125    arguments in ARGV (ARGC of them, minus the program name) for
00126    options given in OPTS.
00127 
00128    Return the option character from OPTS just read.  Return -1 when
00129    there are no more options.  For unrecognized options, or options
00130    missing arguments, `optopt' is set to the option letter, and '?' is
00131    returned.
00132 
00133    The OPTS string is a list of characters which are recognized option
00134    letters, optionally followed by colons, specifying that that letter
00135    takes an argument, to be placed in `optarg'.
00136 
00137    If a letter in OPTS is followed by two colons, its argument is
00138    optional.  This behavior is specific to the GNU `getopt'.
00139 
00140    The argument `--' causes premature termination of argument
00141    scanning, explicitly telling `getopt' that there are no more
00142    options.
00143 
00144    If OPTS begins with `--', then non-option arguments are treated as
00145    arguments to the option '\0'.  This behavior is specific to the GNU
00146    `getopt'.  */
00147 
00148 #ifdef __GNU_LIBRARY__
00149 /* Many other libraries have conflicting prototypes for getopt, with
00150    differences in the consts, in stdlib.h.  To avoid compilation
00151    errors, only prototype getopt for the GNU C library.  */
00152 extern int getopt (int ___argc, char *const *___argv, const char *__shortopts)
00153        __THROW;
00154 #else /* not __GNU_LIBRARY__ */
00155 extern int getopt ();
00156 #endif /* __GNU_LIBRARY__ */
00157 
00158 #ifndef __need_getopt
00159 extern int getopt_long (int ___argc, char *const *___argv,
00160                      const char *__shortopts,
00161                       const struct option *__longopts, int *__longind)
00162        __THROW;
00163 extern int getopt_long_only (int ___argc, char *const *___argv,
00164                           const char *__shortopts,
00165                            const struct option *__longopts, int *__longind)
00166        __THROW;
00167 
00168 #endif
00169 
00170 #ifdef __cplusplus
00171 }
00172 #endif
00173 
00174 /* Make sure we later can get all the definitions and declarations.  */
00175 #undef __need_getopt
00176 
00177 #endif /* getopt.h */