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diff --git a/static/openbsd/man3/getopt_long.3 b/static/openbsd/man3/getopt_long.3 new file mode 100644 index 00000000..88594cbf --- /dev/null +++ b/static/openbsd/man3/getopt_long.3 @@ -0,0 +1,460 @@ +.\" $OpenBSD: getopt_long.3,v 1.25 2022/09/11 06:38:11 jmc Exp $ +.\" $NetBSD: getopt_long.3,v 1.11 2002/10/02 10:54:19 wiz Exp $ +.\" +.\" Copyright (c) 1988, 1991, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)getopt.3 8.5 (Berkeley) 4/27/95 +.\" +.Dd $Mdocdate: September 11 2022 $ +.Dt GETOPT_LONG 3 +.Os +.Sh NAME +.Nm getopt_long , +.Nm getopt_long_only +.Nd get long options from command line argument list +.Sh SYNOPSIS +.In getopt.h +.Vt extern char *optarg; +.Vt extern int optind; +.Vt extern int optopt; +.Vt extern int opterr; +.Vt extern int optreset; +.Ft int +.Fn getopt_long "int argc" "char * const *argv" "const char *optstring" "const struct option *longopts" "int *longindex" +.Ft int +.Fn getopt_long_only "int argc" "char * const *argv" "const char *optstring" "const struct option *longopts" "int *longindex" +.Sh DESCRIPTION +The +.Fn getopt_long +function is similar to +.Xr getopt 3 +but it accepts options in two forms: words and characters. +The +.Fn getopt_long +function provides a superset of the functionality of +.Xr getopt 3 . +.Fn getopt_long +can be used in two ways. +In the first way, every long option understood by the program has a +corresponding short option, and the option structure is only used to +translate from long options to short options. +When used in this fashion, +.Fn getopt_long +behaves identically to +.Xr getopt 3 . +This is a good way to add long option processing to an existing program +with the minimum of rewriting. +.Pp +In the second mechanism, a long option sets a flag in the +.Fa option +structure passed, or will store a pointer to the command line argument +in the +.Fa option +structure passed to it for options that take arguments. +Additionally, the long option's argument may be specified as a single +argument with an equal sign, e.g. +.Bd -literal -offset indent +$ myprogram --myoption=somevalue +.Ed +.Pp +When a long option is processed, the call to +.Fn getopt_long +will return 0. +For this reason, long option processing without +shortcuts is not backwards compatible with +.Xr getopt 3 . +.Pp +It is possible to combine these methods, providing for long options +processing with short option equivalents for some options. +Less frequently used options would be processed as long options only. +.Pp +Abbreviated long option names are accepted when +.Fn getopt_long +processes long options if the abbreviation is unique. +An exact match is always preferred for a defined long option. +.Pp +By default, +.Fn getopt_long +permutes +.Ar argv +such that all option arguments are evaluated before any non-options arguments. +If the first character of +.Fa optstring +is a plus sign +.Pq Ql + +or if the environment variable +.Ev POSIXLY_CORRECT +is set, then +.Ar argv +is processed in order and option processing stops as soon as the first +non-option argument is encountered. +.Pp +The +.Fn getopt_long +call requires an array to be initialized describing the long +options. +Each element of the array is a structure: +.Bd -literal -offset indent +struct option { + char *name; + int has_arg; + int *flag; + int val; +}; +.Ed +.Pp +The +.Fa name +field should contain the option name without the leading double dash. +.Pp +The +.Fa has_arg +field should be one of: +.Pp +.Bl -tag -width "optional_argument" -compact -offset indent +.It Dv no_argument +no argument to the option is expected. +.It Dv required_argument +an argument to the option is required. +.It Dv optional_argument +an argument to the option may be presented. +.El +.Pp +If +.Fa flag +is not +.Dv NULL , +then the integer pointed to by it will be set to the value in the +.Fa val +field. +If the +.Fa flag +field is +.Dv NULL , +then the +.Fa val +field will be returned. +Setting +.Fa flag +to +.Dv NULL +and setting +.Fa val +to the corresponding short option will make this function act just +like +.Xr getopt 3 . +.Pp +If the +.Fa longindex +argument is not +.Dv NULL , +then the integer pointed to by it will be set to the index of the long +option relative to +.Fa longopts . +.Pp +The last element of the +.Fa longopts +array has to be filled with zeroes. +.Pp +The +.Fn getopt_long_only +function behaves identically to +.Fn getopt_long +with the exception that long options may start with +.Sq - +in addition to +.Sq -- . +If an option starting with +.Sq - +does not match a long option but does match a single-character option, +the single-character option is returned. +.Sh RETURN VALUES +If the +.Fa flag +field in +.Vt struct option +is +.Dv NULL , +.Fn getopt_long +and +.Fn getopt_long_only +return the value specified in the +.Fa val +field, which is usually just the corresponding short option. +If +.Fa flag +is not +.Dv NULL , +these functions return 0 and store +.Fa val +in the location pointed to by +.Fa flag . +These functions return +.Sq \&: +if there was a missing option argument, +.Sq \&? +if the user specified an unknown or ambiguous option, and +\-1 when the argument list has been exhausted. +.Sh IMPLEMENTATION DIFFERENCES +This section describes differences to the GNU implementation +found in glibc-2.1.3: +.Bl -bullet +.It +handling of +.Ql - +within the option string (not the first character): +.Bl -tag -width "OpenBSD" +.It GNU +treats a +.Ql - +on the command line as a non-argument. +.It OpenBSD +a +.Ql - +within the option string matches a +.Ql - +(single dash) on the command line. +This functionality is provided for backward compatibility with +programs, such as +.Xr su 1 , +that use +.Ql - +as an option flag. +This practice is wrong, and should not be used in any current development. +.El +.It +handling of +.Ql :: +in the option string in the presence of +.Ev POSIXLY_CORRECT : +.Bl -tag -width "OpenBSD" +.It Both +GNU and +.Ox +ignore +.Ev POSIXLY_CORRECT +here and take +.Ql :: +to mean the preceding option takes an optional argument. +.El +.It +return value in case of missing argument if first character +(after +.Ql + +or +.Ql - ) +in the option string is not +.Ql \&: : +.Bl -tag -width "OpenBSD" +.It GNU +returns +.Ql \&? +.It OpenBSD +returns +.Ql \&: +(since +.Ox Ns 's +.Xr getopt 3 +does). +.El +.It +handling of +.Ql --a +in +.Xr getopt 3 : +.Bl -tag -width "OpenBSD" +.It GNU +parses this as option +.Ql - , +option +.Ql a . +.It OpenBSD +parses this as +.Ql -- , +and returns \-1 (ignoring the +.Ql a ) +(because the original +.Fn getopt +did.) +.El +.It +setting of +.Va optopt +for long options with +.Va flag +.No non- Ns Dv NULL : +.Bl -tag -width "OpenBSD" +.It GNU +sets +.Va optopt +to +.Va val . +.It OpenBSD +sets +.Va optopt +to 0 (since +.Va val +would never be returned). +.El +.It +handling of +.Ql -W +with +.Ql W; +in the option string in +.Xr getopt 3 +(not +.Fn getopt_long ) : +.Bl -tag -width "OpenBSD" +.It GNU +causes a segmentation fault. +.It OpenBSD +no special handling is done; +.Ql W; +is interpreted as two separate options, neither of which take an argument. +.El +.It +setting of +.Va optarg +for long options without an argument that are invoked via +.Ql -W +(with +.Ql W; +in the option string): +.Bl -tag -width "OpenBSD" +.It GNU +sets +.Va optarg +to the option name (the argument of +.Ql -W ) . +.It OpenBSD +sets +.Va optarg +to +.Dv NULL +(the argument of the long option). +.El +.It +handling of +.Ql -W +with an argument that is not (a prefix to) a known long option +(with +.Ql W; +in the option string): +.Bl -tag -width "OpenBSD" +.It GNU +returns +.Ql -W +with +.Va optarg +set to the unknown option. +.It OpenBSD +treats this as an error (unknown option) and returns +.Ql \&? +with +.Va optopt +set to 0 and +.Va optarg +set to +.Dv NULL +(as GNU's man page documents). +.El +.It +The error messages are different. +.It +.Ox +does not permute the argument vector at the same points in +the calling sequence as GNU does. +The aspects normally used by the caller +(ordering after \-1 is returned, value of +.Va optind +relative to current positions) are the same, though. +(We do fewer variable swaps.) +.El +.Sh ENVIRONMENT +.Bl -tag -width Ev +.It Ev POSIXLY_CORRECT +If set, option processing stops when the first non-option is found and +a leading +.Sq + +in the +.Ar optstring +is ignored. +.El +.Sh EXAMPLES +.Bd -literal +int bflag, ch, fd; +int daggerset; + +/* options descriptor */ +static struct option longopts[] = { + { "buffy", no_argument, NULL, 'b' }, + { "fluoride", required_argument, NULL, 'f' }, + { "daggerset", no_argument, &daggerset, 1 }, + { NULL, 0, NULL, 0 } +}; + +bflag = 0; +while ((ch = getopt_long(argc, argv, "bf:", longopts, NULL)) != -1) + switch (ch) { + case 'b': + bflag = 1; + break; + case 'f': + if ((fd = open(optarg, O_RDONLY)) == -1) + err(1, "unable to open %s", optarg); + break; + case 0: + if (daggerset) + fprintf(stderr, "Buffy will use her dagger to " + "apply fluoride to dracula's teeth\en"); + break; + default: + usage(); + } +argc -= optind; +argv += optind; +.Ed +.Sh SEE ALSO +.Xr getopt 3 +.Sh HISTORY +The +.Fn getopt_long +and +.Fn getopt_long_only +functions first appeared in GNU libiberty. +This implementation first appeared in +.Ox 3.3 . +.Sh BUGS +The +.Ar argv +argument is not really +.Dv const +as its elements may be permuted (unless +.Ev POSIXLY_CORRECT +is set). |