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LOOK(1)                   BSD General Commands Manual                  LOOK(1)

NAME
     look -- display lines beginning with a given string

SYNOPSIS
     look [-df] [-t termchar] 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.

     If file is not specified, the file /usr/share/dict/words is used, only alphanumeric characters are com-pared compared
     pared and the case of alphabetic characters is ignored.

     The following options are available:

     -d      Dictionary character set and order, i.e., only alphanumeric characters are compared.

     -f      Ignore the case of alphabetic characters.

     -t      Specify a string termination character, i.e., only the characters in string up to and including
             the first occurrence of termchar are compared.

ENVIRONMENT
     The LANG, LC_ALL and LC_CTYPE environment variables affect the execution of the look utility.  Their
     effect is described in environ(7).

FILES
     /usr/share/dict/words  the dictionary

EXIT STATUS
     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.

COMPATIBILITY
     The original manual page stated that tabs and blank characters participated in comparisons when the -d
     option was specified.  This was incorrect and the current man page matches the historic implementation.

SEE ALSO
     grep(1), sort(1)

HISTORY
     A look utility appeared in Version 7 AT&T UNIX.

BUGS
     Lines are not compared according to the current locale's collating order.  Input files must be sorted
     with LC_COLLATE set to `C'.

BSD                              July 17, 2004                             BSD