xref: /freebsd/usr.bin/look/look.1 (revision c3aac50f284c6cca5b4f2eb46aaa13812cb8b630)
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32.\"     @(#)look.1	8.1 (Berkeley) 6/14/93
33.\" $FreeBSD$
34.\"
35.Dd June 14, 1993
36.Dt LOOK 1
37.Os
38.Sh NAME
39.Nm look
40.Nd display lines beginning with a given string
41.Sh SYNOPSIS
42.Nm
43.Op Fl df
44.Op Fl t Ar termchar
45.Ar string
46.Op Ar file ...
47.Sh DESCRIPTION
48The
49.Nm
50utility displays any lines in
51.Ar file
52which contain
53.Ar string
54as a prefix.
55As
56.Nm
57performs a binary search, the lines in
58.Ar file
59must be sorted.
60.Pp
61If
62.Ar file
63is not specified, the file
64.Pa /usr/share/dict/words
65is used, only alphanumeric characters are compared and the case of
66alphabetic characters is ignored.
67.Pp
68Options:
69.Bl -tag -width Ds
70.It Fl d
71Dictionary character set and order, i.e. only alphanumeric characters
72are compared.
73.It Fl f
74Ignore the case of alphabetic characters.
75.It Fl t
76Specify a string termination character, i.e. only the characters
77in
78.Ar string
79up to and including the first occurrence of
80.Ar termchar
81are compared.
82.El
83.Pp
84The
85.Nm
86utility exits 0 if one or more lines were found and displayed,
871 if no lines were found, and >1 if an error occurred.
88.Sh FILES
89.Bl -tag -width /usr/share/dict/words -compact
90.It Pa /usr/share/dict/words
91the dictionary
92.El
93.Sh SEE ALSO
94.Xr grep 1 ,
95.Xr sort 1
96.Sh COMPATIBILITY
97The original manual page stated that tabs and blank characters participated
98in comparisons when the
99.Fl d
100option was specified.
101This was incorrect and the current man page matches the historic
102implementation.
103.Sh HISTORY
104.Nm Look
105appeared in
106.At v7 .
107