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col - Filters text containing linefeeds
col [-bfhpx] [-l number]
The col command reads from standard input and writes to standard output.
Interfaces documented on this reference page conform to industry standards
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
-b Assumes that the output device in use is not capable of backspacing.
In this case, if two or more characters are to be displayed in the same
position, only the last one that is read is displayed in the output.
This function is useful for converting nroff output to produce readable
results on terminals or printers that do not support underlining or
-f Suppresses the default treatment of half-line motions in the input.
Normally, col does not emit half-line motions on output, although it
does accept them in its input. With this option, output may contain
forward half-linefeeds (<ESC-9>), but not reverse linefeeds (<ESC-7> or
-h [Tru64 UNIX] Compresses spaces into tabs. This is the default.
[Tru64 UNIX] Buffers at least number lines in memory. By default, 128
lines are buffered.
-p Displays unknown escape sequences as characters, subject to
overprinting from reverse line motions. Normally, col ignores them.
You should be fully aware of the textual position of escape sequences
before you use this option.
-x Outputs multiple spaces instead of tabs.
The col command performs the line overlays implied by reverse linefeeds
(ASCII <ESC-7>), and by forward and reverse half-linefeeds (ASCII <ESC-9>
and ASCII <ESC-8>). It also replaces white-space characters with tabs
[Tru64 UNIX] The col command is particularly useful for filtering
multicolumn output made by the nroff and tbl commands.
The col command assumes that the ASCII control characters SO (\017) and SI
(\016) begin and end text in an alternate character set. The col command
remembers the character set each input character belongs to, and on output
generates SI and SO characters as appropriate to ensure that each character
is printed in the correct character set.
On input, the col command accepts only the control characters for the
<Space>, <Backspace>, <Tab>, and <Return> keys; the newline character; the
SI, SO, and VT control characters; and <ESC-7>, <ESC-8>, or <ESC-9>. The
VT control character (\013) is an alternate form of full reverse linefeed
included for compatibility with some earlier programs of this type. The
col command discards all other nonprinting characters.
[Tru64 UNIX] If the input attempts to back up to the last flushed line,
col displays a warning message.
1. Depending on the printer, using the -x option may increase printing
2. Local vertical motion that causes a backwards move over the first line
of input is ignored. The first line of input may not have any
3. This command is marked LEGACY in XCU Issue 5.
The following exit values are returned:
0 Successful completion.
>0 An error occurred.
The following environment variables affect the execution of col:
Provides a default value for the internationalization variables that
are unset or null. If LANG is unset or null, the corresponding value
from the default locale is used. If any of the internationalization
variables contain an invalid setting, the utility behaves as if none of
the variables had been defined.
If set to a non-empty string value, overrides the values of all the
other internationalization variables.
Determines the locale for the interpretation of sequences of bytes of
text data as characters (for example, single-byte as opposed to
multibyte characters in arguments).
Determines the locale for the format and contents of diagnostic
messages written to standard error.
Determines the location of message catalogues for the processing of
Commands: deroff(1), neqn(1), nroff(1), tbl(1)
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