BSFILT(1)BSFILT(1)NAME
bsfilt, colcrt - a colcrt-like backspace filter
SYNOPSIS
bsfilt [ - ] [ -U ] [ file ... ]
DESCRIPTION
Bsfilt filters backspace sequences from the input file(s) (standard
input if none) in an approximation of colcrt(1). Both the backspace
and the character it returns to are removed, unless they form an under‐
line sequence. Underline sequences are treated according to the set‐
tings of the - and -U options.
OPTIONS
- specifies that no underlining of any kind is to be propagated.
Without this option or the -U option, bsfilt approximates under‐
lining with minus signs (`-') in following lines.
-U specifies that underlining with underscore (`_') and backspace
(`) character sequences is permitted.
SEE ALSOcawf(1), colcrt(1) and nroff(1).
DIAGNOSTICS
Diagnostic messages are delivered to the standard error file.
HISTORY
Vic Abell of Purdue University wrote bsfilt to have a backspace filter
for cawf(1) that is independent of licensed source code.
BUGS
The maximum length of a line that can be underlined with minus signs is
fixed.
Bsfilt does not examine the characters that are being overprinted via
backspace operations. Thus, overprinting that is intended to form a
new character from several different ones is ineffective and only the
last character of the sequence is propagated - e. g., ``o^H+'',
intended to look like a bullet, is reduced to `+'.
February, 1991 BSFILT(1)