1.\" Copyright (c) 1990, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)look.1 8.1 (Berkeley) 6/14/93 33.\" 34.Dd June 14, 1993 35.Dt LOOK 1 36.Os 37.Sh NAME 38.Nm look 39.Nd display lines beginning with a given string 40.Sh SYNOPSIS 41.Nm look 42.Op Fl df 43.Op Fl t Ar termchar 44.Ar string 45.Op Ar file 46.Sh DESCRIPTION 47The 48.Nm look 49utility displays any lines in 50.Ar file 51which contain 52.Ar string 53as a prefix. 54As 55.Nm look 56performs a binary search, the lines in 57.Ar file 58must be sorted. 59.Pp 60If 61.Ar file 62is not specified, the file 63.Pa /usr/share/dict/words 64is used, only alphanumeric characters are compared and the case of 65alphabetic characters is ignored. 66.Pp 67Options: 68.Bl -tag -width Ds 69.It Fl d 70Dictionary character set and order, i.e. only alphanumeric characters 71are compared. 72.It Fl f 73Ignore the case of alphabetic characters. 74.It Fl t 75Specify a string termination character, i.e. only the characters 76in 77.Ar string 78up to and including the first occurrence of 79.Ar termchar 80are compared. 81.El 82.Pp 83The 84.Nm look 85utility exits 0 if one or more lines were found and displayed, 861 if no lines were found, and >1 if an error occurred. 87.Sh FILES 88.Bl -tag -width /usr/share/dict/words -compact 89.It Pa /usr/share/dict/words 90the dictionary 91.El 92.Sh SEE ALSO 93.Xr grep 1 , 94.Xr sort 1 95.Sh COMPATIBILITY 96The original manual page stated that tabs and blank characters participated 97in comparisons when the 98.Fl d 99option was specified. 100This was incorrect and the current man page matches the historic 101implementation. 102.Sh HISTORY 103.Nm Look 104appeared in Version 7 AT&T Unix. 105