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col(1) [v7 man page]

COL(1)							      General Commands Manual							    COL(1)

NAME
col - filter reverse line feeds SYNOPSIS
col [-bfx] DESCRIPTION
Col reads the standard input and writes the standard output. It performs the line overlays implied by reverse line feeds (ESC-7 in ASCII) and by forward and reverse half line feeds (ESC-9 and ESC-8). Col is particularly useful for filtering multicolumn output made with the `.rt' command of nroff and output resulting from use of the tbl(1) preprocessor. Although col accepts half line motions in its input, it normally does not emit them on output. Instead, text that would appear between lines is moved to the next lower full line boundary. This treatment can be suppressed by the -f (fine) option; in this case the output from col may contain forward half line feeds (ESC-9), but will still never contain either kind of reverse line motion. If the -b option is given, col assumes that the output device in use is not capable of backspacing. In this case, if several characters are to appear in the same place, only the last one read will be taken. The control characters SO (ASCII code 017), and SI (016) are assumed to start and end text in an alternate character set. The character set (primary or alternate) associated with each printing character read is remembered; on output, SO and SI characters are generated where necessary to maintain the correct treatment of each character. Col normally converts white space to tabs to shorten printing time. If the -x option is given, this conversion is suppressed. All control characters are removed from the input except space, backspace, tab, return, newline, ESC (033) followed by one of 789, SI, SO, and VT (013). This last character is an alternate form of full reverse line feed, for compatibility with some other hardware conventions. All other non-printing characters are ignored. SEE ALSO
troff(1), tbl(1), greek(1) BUGS
Can't back up more than 128 lines. No more than 800 characters, including backspaces, on a line. COL(1)

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COL(1)							    BSD General Commands Manual 						    COL(1)

NAME
col -- filter reverse line feeds from input SYNOPSIS
col [-bfpx] [-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 fol- lowing line. -p Force unknown control sequences to be passed through unchanged. Normally, col will filter out any control sequences from the input other than those recognized and interpreted by itself, which are listed below. -x Output multiple spaces instead of tabs. -l num 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 alternative 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
expand(1), nroff(1), tbl(1) STANDARDS
The col utility conforms to X/Open Portability Guide Issue 4, Version 2 (``XPG4.2''). The -l option is an extension to the standard. HISTORY
A col command appeared in Version 6 AT&T UNIX. BSD
February 22, 1999 BSD
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