.\" Copyright (c) 1990 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" %sccs.include.redist.man%
.\"
.\"     @(#)look.1	6.6 (Berkeley) %G%
.\"
.Dd 
.Dt LOOK 1
.Os
.Sh NAME
.Nm look
.Nd display lines beginning with a given string
.Sh SYNOPSIS
.Nm look
.Op Fl df
.Ar string
.Op Ar file
.Sh DESCRIPTION
The 
.Nm look
utility displays any lines in
.Ar file
which contain
.Ar string
as a prefix.
As
.Nm look
performs a binary search, the lines in
.Ar file
must be sorted.
.Pp
If
.Ar file
is not specified, the file
.Pa /usr/share/dict/words
is used, only alphanumeric characters are compared and the case of
alphabetic characters is ignored.
.Pp
Options:
.Bl -tag -width Ds
.It Fl d
Dictionary character set and order, i.e. only alphanumeric characters
are compared.
.It Fl f
Ignore the case of alphabetic characters.
.El
.Pp
The
.Nm 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.
.Sh FILES
.Bl -tag -width /usr/share/dict/words -compact
.It Pa /usr/share/dict/words
the dictionary
.El
.Sh SEE ALSO
.Xr grep 1 ,
.Xr sort 1
.Sh COMPATIBILITY
The original manual page stated that tabs and blank characters participated
in comparisons when the
.Fl d
option was specified.
This was incorrect and the current man page matches the historic
implementation.
.Sh HISTORY
.Nm Look
appeared in Version 7 AT&T Unix.