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LOOK(1)                       User Commands                       LOOK(1)

NAME
       look - display lines beginning with a given string

SYNOPSIS
       look [options] string [file]

DESCRIPTION
       The  look utility displays any lines in file which contain string.
       As look performs a binary search, the lines in file must be sorted
       (where  sort(1)  was given the same options -d and/or -f that look
       is invoked with).

       If file is not specified, the file /usr/share/dict/words is  used,
       only  alphanumeric  characters are compared and the case of alpha‐
       betic characters is ignored.

OPTIONS
       -a, --alternative
              Use the alternative dictionary file.

       -d, --alphanum
              Use normal dictionary character set and order,  i.e.,  only
              blanks  and  alphanumeric characters are compared.  This is
              on by default if no file is specified.

              Note that blanks have been added  to  dictionary  character
              set  for  compatibility  with sort -d command since version
              2.28.

       -f, --ignore-case
              Ignore the case of alphabetic characters.  This  is  on  by
              default if no file is specified.

       -t, --terminate character
              Specify  a  string  termination  character,  i.e., only the
              characters in string up to and including the  first  occur‐
              rence of character are compared.

       -V, --version
              Display version information and exit.

       -h, --help
              Display help text and exit.

       The  look utility exits 0 if one or more lines were found and dis‐
       played, 1 if no lines were found, and >1 if an error occurred.

EXAMPLE
              sort -d /etc/passwd -o /tmp/look.dict
              look -t: root:foobar /tmp/look.dict

ENVIRONMENT
       WORDLIST
              Path to a dictionary file.  The  environment  variable  has
              greater  priority than the dictionary path defined in FILES
              segment.

FILES
       /usr/share/dict/words
           the dictionary

       /usr/share/dict/web2
           the alternative dictionary

SEE ALSO
       grep(1), sort(1)

HISTORY
       The look utility appeared in Version 7 AT&T Unix.

AVAILABILITY
       The look command is part of the util-linux package and  is  avail‐
       able from https://www.kernel.org/pub/linux/utils/util-linux/.

util-linux                      June 2011                         LOOK(1)