AT&T UNIX™PC Unix System V Users Manual - tenox

Document Preparation, Version 3.51
In order to prevent this error, italics have been disabled by leaving the
"iton" and "itoff' definitions in the printer driving tables empty. Nroff
sees the empty definitions and proceeds to underline text instead of
italicizing it.
If you wish to use italics with your printer, enter your printer's italicize
commands in the appropriate printer driving table and then invoke the
mm or nroff command with the -rUt flag for any documents which
contain italicized text. This will force emphasizing of headings to the
non-continuous style (only letters and digits will be italicized while
spaces will be left blank).
Important Information 21