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expand(1)

ksh(1)

tabs(1)

unexpand(1)                                                     unexpand(1)

NAME
     unexpand - convert spaces to tabs

SYNOPSIS
     /usr/ucb/unexpand[ -a| -t tablist][ file]...

DESCRIPTION
     The unexpand commands writes files or the standard input to the stan-
     dard output, with blanks at the beginning of each line converted to
     the maximum number of tabs, followed by the minimum number of blanks
     needed to pad the line to the next tab stop, which were originally
     filled by the converted characters. A tab stop is set after every 8
     column positions by default. All backspace characters are copied to
     the output and cause the column position count for for tab stop calcu-
     lations to be decremented. The column position count will not be
     decremented below zero.

OPTIONS
     -a   Not only are the blanks at the start of each line converted, but
          also all sequences of two or more blanks directly in front of a
          tab stop are converted into the maximum number of tabs followed
          by the minimum number of blanks needed to pad the line to the
          next tab stop, which were originally filled by the converted
          characters.

     -t tablist
          Specifies the tab stops. The argument tablist must consist of one
          or more numbers, separated by blanks or commas, in ascending
          order. A list separated by blanks must be enclosed in quotes. If
          only one number is specified, the tab stops will be set to
          tablist column positions instead of the default 8 column posi-
          tions. If multiple numbers are given, the tabs will be set at the
          specified column positions.

          Each tab stop position N must be an integer value greater than
          zero, and the specifications must be in ascending order. This
          means that tabbing from the start of the line of output to posi-
          tion N causes the next character output to be in the (N+1)th
          column position in that line.

          For characters that are one position behind the last position
          defined in a list with multiple tab stops, there is no conversion
          of blanks into tabs.

          If -t is specified, conversion of blanks is not restricted to the
          leading blanks. -a is ignored in this case.

     file The file whose blanks are to be replaced by tab characters.







Page 1                       Reliant UNIX 5.44                Printed 11/98

unexpand(1)                                                     unexpand(1)

ENVIRONMENT VARIABLES
     The following environment variables affect the execution of unexpand:

     LANG         Specifies a default value for the internationalization
                  variables that are unset or null. If LANG is unset or
                  null, the corresponding default value from the interna-
                  tionalized environment is used. If one of the interna-
                  tionalization variables contains an invalid setting, the
                  command behaves as if none of the variables have been
                  defined.

     LCALL       If this variable has been assigned a value, i.e. it is
                  not a null string, this value overrides the values of all
                  the other internationalization variables.

     LCCTYPE     Determines the internationalized environment for the
                  interpretation of byte sequences (e.g. single-byte char-
                  acters as opposed to multi-byte characters in arguments
                  and input files). The internationalized environment for
                  the processing of tab characters and blanks and for the
                  specification of the width in column positions each char-
                  acter would occupy on a constant-width output device.

     LCMESSAGES  Determines the format and contents of error messages.

     NLSPATH      Determines the position of message catalogs for the pro-
                  cessing of LCMESSAGES.

STANDARD OUTPUT (STDOUT)
     The standard output is equivalent to the input files with blanks con-
     verted into the appropriate number of tabs.

APPLICATION USAGE
     The default behavior of unexpand, whereby only leading blanks are
     taken into consideration, may not be desired in some cases. Users who
     always want to convert all blanks in a file should use an alias defin-
     ition [see ksh(1)] to create a version of unexpand that is always
     called with the options -a or -t 8.

EXIT STATUS
     0    Successful completion.

     >0   An error occurred.

SEE ALSO
     expand(1), ksh(1), tabs(1).








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