ul(1) — Linux manual page


UL(1)                         User Commands                        UL(1)

NAME         top

       ul - do underlining

SYNOPSIS         top

       ul [options] [file...]

DESCRIPTION         top

       ul reads the named files (or standard input if none are given)
       and translates occurrences of underscores to the sequence which
       indicates underlining for the terminal in use, as specified by
       the environment variable TERM. The terminfo database is read to
       determine the appropriate sequences for underlining. If the
       terminal is incapable of underlining but is capable of a standout
       mode, then that is used instead. If the terminal can overstrike,
       or handles underlining automatically, ul degenerates to cat(1).
       If the terminal cannot underline, underlining is ignored.

OPTIONS         top

       -i, --indicated
           Underlining is indicated by a separate line containing
           appropriate dashes `-'; this is useful when you want to look
           at the underlining which is present in an nroff output stream
           on a crt-terminal.

       -t, -T, --terminal terminal
           Override the environment variable TERM with the specified
           terminal type.

       -h, --help
           Display help text and exit.

       -V, --version
           Print version and exit.

ENVIRONMENT         top

       The following environment variable is used:

           The TERM variable is used to relate a tty device with its
           device capability description (see terminfo(5)). TERM is set
           at login time, either by the default terminal type specified
           in /etc/ttys or as set during the login process by the user
           in their login file (see setenv(3)).

HISTORY         top

       The ul command appeared in 3.0BSD.

BUGS         top

       nroff usually outputs a series of backspaces and underlines
       intermixed with the text to indicate underlining. No attempt is
       made to optimize the backward motion.

SEE ALSO         top

       colcrt(1), login(1), man(1), nroff(1), setenv(3), terminfo(5)

REPORTING BUGS         top

       For bug reports, use the issue tracker at

AVAILABILITY         top

       The ul command is part of the util-linux package which can be
       downloaded from Linux Kernel Archive
       <https://www.kernel.org/pub/linux/utils/util-linux/>. This page
       is part of the util-linux (a random collection of Linux
       utilities) project. Information about the project can be found at
       ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩. If you have
       a bug report for this manual page, send it to
       util-linux@vger.kernel.org. This page was obtained from the
       project's upstream Git repository
       ⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
       2023-12-22. (At that time, the date of the most recent commit
       that was found in the repository was 2023-12-14.) 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

util-linux 2.39.594-1e0ad      2023-07-19                          UL(1)

Pages that refer to this page: colcrt(1)