.TH COL 1  col
.SH NAME
col - filter reverse line-feeds
.SH SYPNOSIS
.B col
.RB [ \-p ]
.RB [ \-b ]
.RB [ \-f ]
.RB [ \-x ]
.RB [ \-l
.IR num ]
.SH DESCRIPTION
.PP
The
.B col
utility filter all the reverse (and half reverse) line feeds,
as they are produced by nroff with .2C of ms(6) or by tbl(1).
.B col
also replaces spaces by tabs when it is possible.
The control sequences managed by
.B col
are:
.TP
.B ESC-7
reverse line-feed
.TP
.B ESC-8
reverse half-line-feed
.TP
.B ESC-9
forward half-line-feed
.TP
.B VT
vertical-tab
.TP
.B SP
Space
.TP
.B TAB
horizontal tab
.TP
.B RETURN
Carriage return
.TP
.B NL
New line
.PP
All the other control codes and escape sequences are removed.
.B Col
transform all the spaces into tabulators.
.SH OPTIONS
.TP
.B \-p
Print unknown escape sequences to the output.
.TP
.B \-b
Do not print backspaces in output,
and Print only the last overstriked character in the output.
.TP
.B \-f
Allow forward half line feeds in the output.
.TP
.B \-x
Do not convert spaces in tabulators.
.TP
.BI \-l " num"
Increment to
.I num
the number of lines buffered for
.B col.
.SH BUGS
.PP
.B Col
only process text with a maximum of 256 lines with 800 characteres per line,
although the number of lines can be modified with
.B \-l
option.
When the number of lines is bigger,
the buffer is flushed to the output,
so new reverse line feeds can not operate in the flushed  lines.
This implementation ignores SI and SO selection character sets,
because it is supposed it will work only with UTF-8 strings,
although the UTF-8 support is missed.
.SH SEE ALSO
.BR nroff (1),
.BR ms (6),
.BR tbl(1).