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 a
       prefix. 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 alphabetic
       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 occurrence of character are
           compared.

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

       -V, --version
           Print version and exit.

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

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

FILES
       /usr/share/dict/words
           the dictionary

       /usr/share/dict/web2
           the alternative dictionary

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

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

SEE ALSO
       grep(1), sort(1)

REPORTING BUGS
       For bug reports, use the issue tracker at
       <https://github.com/util-linux/util-linux/issues>.

AVAILABILITY
       The look command is part of the util-linux package which can be
       downloaded from Linux Kernel Archive
       <https://www.kernel.org/pub/linux/utils/util-linux/>.

util-linux 2.40                   2024-04-06                           LOOK(1)