man7.org > Linux > man-pages

Linux/UNIX system programming training

getopt_long_only(3) — Linux manual page

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | ATTRIBUTES | STANDARDS | SEE ALSO | COLOPHON 

getopt_long_only(3)      Library Functions Manual     getopt_long_only(3)

NAME         top

       getopt_long_only - parse long command-line options

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #define _GNU_SOURCE
       #include <getopt.h>

       int getopt_long_only(int argc, char *argv[],
                  const char *optstring,
                  const struct option *longopts, int *longindex);

DESCRIPTION         top

       getopt_long_only() is like getopt_long(3), but '-' as well as "--"
       can indicate a long option.  If an option that starts with '-'
       (not "--") doesn't match a long option, but does match a short
       option, it is parsed as a short option instead.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       โ”Œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ฌโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ฌโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”
       โ”‚ Interface          โ”‚ Attribute     โ”‚ Value                     โ”‚
       โ”œโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ผโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ค
       โ”‚ getopt_long_only() โ”‚ Thread safety โ”‚ MT-Unsafe race:getopt env โ”‚
       โ””โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ดโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”ดโ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”€โ”˜

STANDARDS         top

       GNU.

SEE ALSO         top

       getopt(1), getopt(3), getopt_long(3), getsubopt(3)

COLOPHON         top

       This page is part of the man-pages (Linux kernel and C library
       user-space interface documentation) project.  Information about
       the project can be found at 
       โŸจhttps://www.kernel.org/doc/man-pages/โŸฉ.  If you have a bug report
       for this manual page, see
       โŸจhttps://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTINGโŸฉ.
       This page was obtained from the tarball man-pages-6.18.tar.gz
       fetched from
       โŸจhttps://mirrors.edge.kernel.org/pub/linux/docs/man-pages/โŸฉ on
       2026-05-24.  If you discover any rendering problems in this HTML
       version of the page, or you believe there is a better or more up-
       to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not
       part of the original manual page), send a mail to
       man-pages@man7.org

Linux man-pages 6.18            2025-12-07            getopt_long_only(3)

Pages that refer to this page: getopt(3),  getopt_long(3)

HTML rendering created 2026-05-30 by Michael Kerrisk, author of The Linux Programming Interface.

For details of in-depth Linux/UNIX system programming training courses that I teach, look here.

Hosting by jambit GmbH.

Cover of TLPI