xref: /dragonfly/usr.bin/look/look.1 (revision 36a3d1d6)
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32.\"     @(#)look.1	8.1 (Berkeley) 6/14/93
33.\" $FreeBSD: src/usr.bin/look/look.1,v 1.6.2.3 2002/06/21 15:27:58 charnier Exp $
34.\" $DragonFly: src/usr.bin/look/look.1,v 1.3 2006/02/17 19:39:09 swildner Exp $
35.\"
36.Dd June 14, 1993
37.Dt LOOK 1
38.Os
39.Sh NAME
40.Nm look
41.Nd display lines beginning with a given string
42.Sh SYNOPSIS
43.Nm
44.Op Fl df
45.Op Fl t Ar termchar
46.Ar string
47.Op Ar
48.Sh DESCRIPTION
49The
50.Nm
51utility displays any lines in
52.Ar file
53which contain
54.Ar string
55as a prefix.
56As
57.Nm
58performs a binary search, the lines in
59.Ar file
60must be sorted.
61.Pp
62If
63.Ar file
64is not specified, the file
65.Pa /usr/share/dict/words
66is used, only alphanumeric characters are compared and the case of
67alphabetic characters is ignored.
68.Pp
69Options:
70.Bl -tag -width Ds
71.It Fl d
72Dictionary character set and order, i.e. only alphanumeric characters
73are compared.
74.It Fl f
75Ignore the case of alphabetic characters.
76.It Fl t
77Specify a string termination character, i.e. only the characters
78in
79.Ar string
80up to and including the first occurrence of
81.Ar termchar
82are compared.
83.El
84.Pp
85The
86.Nm
87utility exits 0 if one or more lines were found and displayed,
881 if no lines were found, and >1 if an error occurred.
89.Sh FILES
90.Bl -tag -width /usr/share/dict/words -compact
91.It Pa /usr/share/dict/words
92the dictionary
93.El
94.Sh COMPATIBILITY
95The original manual page stated that tabs and blank characters participated
96in comparisons when the
97.Fl d
98option was specified.
99This was incorrect and the current man page matches the historic
100implementation.
101.Sh SEE ALSO
102.Xr grep 1 ,
103.Xr sort 1
104.Sh HISTORY
105A
106.Nm
107utility appeared in
108.At v7 .
109