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col(1) [bsd man page]

COL(1)							      General Commands Manual							    COL(1)

NAME
col - filter reverse line feeds SYNOPSIS
col [ -bfh ] 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. If the -h option is given, col converts white space to tabs to shorten printing time. All control characters are removed from the input except space, backspace, tab, return, newline, ESC (033) followed by one of 7, 8, 9, SI, SO, and VT (013). This last character is an alternate form of full reverse line feed, for compatibility with some other hardware conven- tions. All other non-printing characters are ignored. SEE ALSO
troff(1), tbl(1) BUGS
Can't back up more than 128 lines. No more than 800 characters, including backspaces, on a line. 7th Edition May 16, 1986 COL(1)

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col(1)								   User Commands							    col(1)

NAME
col - reverse line-feeds filter SYNOPSIS
col [-bfpx] DESCRIPTION
The col utility reads from the standard input and writes to the standard output. It performs the line overlays implied by reverse line- feeds, and by forward and reverse half-line-feeds. Unless -x is used, all blank characters in the input will be converted to tab charac- ters wherever possible. col is particularly useful for filtering multi-column output made with the .rt command of nroff(1) and output resulting from use of the tbl(1) preprocessor. The ASCII control characters SO and SI are assumed by col to start and end text in an alternative character set. The character set to which each input character belongs is remembered, and on output SI and SO characters are generated as appropriate to ensure that each character is written in the correct character set. On input, the only control characters accepted are space, backspace, tab, carriage-return and newline characters, SI, SO, VT, reverse line- feed, forward half-line-feed and reverse half-line-feed. The VT character is an alternative form of full reverse line-feed, included for compatibility with some earlier programs of this type. The only other characters to be copied to the output are those that are printable. The ASCII codes for the control functions and line-motion sequences mentioned above are as given in the table below. ESC stands for the ASCII escape character, with the octal code 033; ESC- means a sequence of two characters, ESC followed by the character x. reverse line-feed ESC-7 reverse half-line-feed ESC-8 forward half-line-feed ESC-9 vertical-tab (VT) 013 start-of-text (SO) 016 end-of-text (SI) 017 OPTIONS
-b Assume that the output device in use is not capable of backspacing. In this case, if two or more characters are to appear in the same place, only the last one read will be output. -f 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. -p Normally, col will ignore any escape sequences unknown to it that are found in its input; the -p option may be used to cause col to output these sequences as regular characters, subject to overprinting from reverse line motions. The use of this option is highly discouraged unless the user is fully aware of the textual position of the escape sequences. -x Prevent col from converting blank characters to tab characters on output wherever possible. Tab stops are considered to be at each column position n such that n modulo 8 equals 1. ENVIRONMENT VARIABLES
See environ(5) for descriptions of the following environment variables that affect the execution of col: LC_CTYPE, LC_MESSAGES, and NLSPATH. EXIT STATUS
The following error values are returned: 0 Successful completion. >0 An error occurred. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWesu | +-----------------------------+-----------------------------+ |CSI |enabled | +-----------------------------+-----------------------------+ SEE ALSO
nroff(1), tbl(1), ascii(5), attributes(5), environ(5) NOTES
The input format accepted by col matches the output produced by nroff with either the -T37 or -Tlp options. Use -T37 (and the -f option of col) if the ultimate disposition of the output of col will be a device that can interpret half-line motions, and -Tlp otherwise. col cannot back up more than 128 lines or handle more than 800 characters per line. Local vertical motions that would result in backing up over the first line of the document are ignored. As a result, the first line must not have any superscripts. SunOS 5.10 1 Feb 1995 col(1)

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