There are two escapes that give information directly to the postprocessor. This is particularly useful for embedding POSTSCRIPT into the final document.
Embeds its argument into the
gtroff output preceded with
\: are ignored
\X, ‘\ ’ and
\~ are converted to single
space characters. All other escapes (except
\\, which produces a
backslash) cause an error.
device request simply processes its
argument in copy mode (see Copy-in Mode).
If the ‘use_charnames_in_special’ keyword is set in the DESC
file, special characters no longer cause an error; they are simply
output verbatim. Additionally, the backslash is represented as
‘use_charnames_in_special’ is currently used by
This is approximately equivalent to ‘\X'\*[name]'’
(one-character name n, two-character name nm).
However, the contents of the string or macro name are not
interpreted; also it is permitted for name to have been defined as
a macro and thus contain newlines (it is not permitted for the argument
\X to contain newlines). The inclusion of newlines requires
an extension to the Unix
troff output format, and confuses
drivers that do not know about this extension (see Device Control Commands).
See Output Devices.