Content-type: text/html Man page of expand

expand

Section: User Commands (1)
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NAME

expand, unexpand - Replaces tab characters with spaces or spaces with tab characters  

SYNOPSIS


 

Current syntax

expand [-t tablist] [file...]

unexpand [-a|-t tablist] [file...]


 

Obsolescent syntax

expand [-tabstop|-tab1,tab2,...,tabn] [file...]


 

STANDARDS

Interfaces documented on this reference page conform to industry standards as follows:

expand:  XPG4, XPG4-UNIX

unexpand:  XPG4, XPG4-UNIX

Refer to the standards(5) reference page for more information about industry standards and associated tags.
 

OPTIONS

Replaces spaces at the beginning of each line with a tab, and inserts tab characters wherever their presence compresses the resultant file by replacing two or more characters. When the -t option is specified with the unexpand command, the -a option has no effect. (This option applies to the unexpand command only.) Specifies the tab stops. The tablist argument consists of a single positive decimal integer or multiple positive decimal integers, separated by spaces or commas, in ascending order. If a single number is specified, tabs are set tablist column positions apart instead of the default (8). If multiple numbers are specified, tabs are set at those specific column positions. Tabbing to tab stop position n thus causes the next character output to be in the (n+1)th column position on that line.

If expand has to process a tab character at a position beyond the last of those specified in a multiple tab stop list, the tab character is replaced by a single space in the output. Sets tab stops tabstop spaces apart instead of the default (8). (Obsolescent) Sets tab stops at specified columns. (Obsolescent)
[Compaq]  Columns are measured in bytes.
 

OPERANDS

The path name of a file to be processed. If you do not specify this operand, standard input is read.
 

DESCRIPTION

The expand command changes tab characters to spaces in the named files, or the standard input, and writes the result to the standard output.

The unexpand command puts tab characters into the data from the standard input, or the named files, and writes the result to the standard output.

Backspace characters are preserved in the output and decrement the column count for tab calculations. The column position count cannot be decremented below one. The expand command is useful for preprocessing character files (before sorting, looking at specific columns, and so on.) that contain tab characters.

By default, unexpand converts only spaces that are within sequences of spaces and tab characters at the beginnings of lines. Use -a to convert other sequences of spaces.
 

NOTES

If the expand command encounters difficulties opening any specified file, it writes an error message to standard error and terminates immediately with an error status.

If the unexpand command encounters difficulties opening any specified file, it writes an error message to standard error and continues operation. The exit status will reflect the error.
 

EXIT STATUS

The following exit values are returned by either command: Successful completion. An error occurred.
 

EXAMPLES

To replace tab characters in file with spaces, enter: expand file To replace the spaces in file with tab characters, enter: unexpand -a file


 

ENVIRONMENT VARIABLES

The following environment variables affect the execution of expand and unexpand: 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 LC_MESSAGES.
 

SEE ALSO

Commands:  fold(1), tabs(1)

Standards:  standards(5)


 

Index

NAME
SYNOPSIS
Current syntax
Obsolescent syntax
STANDARDS
OPTIONS
OPERANDS
DESCRIPTION
NOTES
EXIT STATUS
EXAMPLES
ENVIRONMENT VARIABLES
SEE ALSO

This document was created by man2html, using the manual pages.
Time: 02:42:47 GMT, October 02, 2010