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LOOK(1) 		     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 pre-
     fix.  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  al-
     phanumeric characters are compared and the case of alphabetic characters is
     ignored.

     The following options are available:

     -d, --alphanum
	     Dictionary character set and order, i.e., only alphanumeric charac-
	     ters are compared.

     -f, --ignore-case
	     Ignore the case of alphabetic characters.

     -t, --terminate termchar
	     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.

EXAMPLES
     Look for lines starting with `xylen' in the file /usr/share/dict/words:

	   $ look xylen
	   xylene
	   xylenol
	   xylenyl

     Same as above, but do not consider any  characters  in  string  beyond  the
     first  `e'.   Note  that  -f is implicit since we are searching the default
     file /usr/share/dict/words:

	   $ look -t e xylen
	   Xyleborus
	   xylem
	   xylene
	   xylenol
	   xylenyl
	   xyletic

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.

     The -a and --alternative flags are ignored for compatibility.

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'.

FreeBSD 15.1			December 29, 2020			 LOOK(1)

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