UL(1) BSD General Commands Manual UL(1)
ul — do underlining
ul [-i] [-t terminal] [file …]
The ul utility 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 envi‐
ronment variable TERM. The file /etc/termcap 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. If the terminal cannot underline, underlining is
ignored. During the translation some other special characters also get
translated. E.g. TAB gets expanded to spaces.
The following options are available:
-i Underlining is indicated by a separate line containing appropri‐
ate dashes ‘-’; this is useful when you want to look at the
underlining which is present in an nroff output stream on a
Overrides the terminal type specified in the environment with
The LANG, LC_ALL, LC_CTYPE and TERM environment variables affect the exe‐
cution of ul as described in environ(7).
The ul utility exits 0 on success, and >0 if an error occurs.
The ul command appeared in 3.0BSD.
The nroff command usually outputs a series of backspaces and under‐
lines intermixed with the text to indicate underlining. No attempt is
made to optimize the backward motion.
BSD August 4, 2004 BSD