col - filter reverse line feeds from input
col [-bfhx] [-l num]
col filters out reverse (and half-reverse) line feeds so
that the output
is in the correct order with only forward and half-forward
and replaces whitespace 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
The options are as follows:
-b Do not output any backspaces, printing only the last
written to each column position.
-f Forward half-line feeds are permitted (``fine''
characters printed on a half-line boundary are
printed on the
-h Compress spaces into tabs. This is the default behavior.
-x Output multiple spaces instead of tabs.
-l num Buffer at least num lines in memory. By default,
128 lines are
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-10 Half reverse line feed (escape then 10).
ESC-11 Half forward line feed (escape then 11).
backspace Moves back one column (8); ignored in the
carriage return (13)
newline Forward line feed (10); also does carriage
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
col keeps track of the character set as characters are read
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.
expand(1), nroff(1), tbl(1)
A col command appeared in Version 6 AT&T UNIX.
OpenBSD 3.6 June 29, 1993
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