ul [ -i ] [ -t Terminal ] [ File ... ]
The ul command reads the named files specified by the File parameter (or standard input if no file is given) and translates occurrences of underscores to the sequence that indicates underlining for the terminal in use, as specified by the TERM environment variable.
| -i | Causes the ul command to indicate underlining by a separate line containing appropriate _ (underline characters). Use this to see the underlining present in an nroff command output stream on a CRT terminal. |
| -t Terminal | Overrides the terminal type specified in the environment. The terminfo file 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 mode is used
instead. If the terminal can overstrike or automatically underline, the
ul command acts like the cat command and displays on the
screen. If the terminal cannot underline and no alternatives are
available, underlining is ignored.
If the -t flag is not specified, the ul command translates for the terminal type specified by the TERM environment variable. If the value of the Terminal variable is not a valid terminal type, the ul command translates for a dumb terminal. |
| /usr/share/lib/terminfo/* | Contains the terminal capabilities database. |
The cat command, colcrt command, man command, nroff command.
The terminfo file.