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tbl(1)

nroff(1)

col(1)

Name

col − filter reverse line feeds

Syntax

col [−options]

Description

The col command 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, respectively). The col command is particularly useful for filtering multicolumn output made with the .rt command of nroff, and for filtering output resulting from the tbl preprocessor.

Although col accepts half line motions in its input, it does not normally output them. Instead, text that would appear between lines is moved to the next lower full line boundary.

The control characters SO (ASCII code 017) and SI (ASCII code 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. 

The col command normally converts white space to tabs to shorten printing time. If the −h option is given, this conversion is suppressed. 

On input, the only control characters accepted are <space>, <backspace>, <tab>, <return>, <newline>, etc...  The VT character is an alternate form of full reverse linefeed, included for compatibility with earlier programs of this type. All other non-printing characters are ignored. 

Options

−bAssumes that the output device does not have backspacing. 

−fSuppresses moving half lines to the next full line. 

−hSuppresses conversion of white space to tabs. 

−pForces through unchanged any unknown escape sequences that are found in its input. This option should be used with care. 

−xSuppresses conversion of white space to tabs (same as −h). 

Restrictions

Cannot back up more than 128 lines. 
No more than 800 characters, including backspaces, on a line.

See Also

tbl(1), nroff(1)

Typewritten Software • bear@typewritten.org • Edmonds, WA 98026