NAME
col —
filter reverse line feeds from
input
SYNOPSIS
col |
[-bfx] [-l
num] |
DESCRIPTION
Col filters out reverse (and half reverse) line feeds so
that the output is in the correct order with only forward and half forward
line feeds, and replaces white-space characters with tabs where possible. This
can be useful in processing the output of
nroff(1) and tbl(1).
Col reads from the standard input and
writes to the standard output.
The options are as follows:
-b- Do not output any backspaces, printing only the last character written to each column position.
-f- Forward half line feeds are permitted (``fine'' mode). Normally characters printed on a half line boundary are printed on the following line.
-x- Output multiple spaces instead of tabs.
-lnum- Buffer at least num lines in memory. By default, 128 lines are buffered.
The control sequences for carriage motion that
col understands and their decimal values are listed
in the following table:
- ESC-7
- reverse line feed (escape then 7)
- ESC-8
- half reverse line feed (escape then 8)
- ESC-9
- half forward line feed (escape then 9)
- backspace
- moves back one column (8); ignored in the first column
- carriage return
- (13)
- newline
- forward line feed (10); also does carriage return
- shift in
- shift to normal character set (15)
- shift out
- shift to alternate character set (14)
- space
- moves forward one column (32)
- tab
- moves forward to next tab stop (9)
- vertical tab
- reverse line feed (11)
All unrecognized control characters and escape sequences are discarded.
Col keeps track of the character set as
characters are read and makes sure the character set is correct when they
are output.
If the input attempts to back up to the last flushed line,
col will display a warning message.
SEE ALSO
HISTORY
A col command appeared in Version 6
AT&T UNIX.