xref: /freebsd/usr.bin/look/look.1 (revision 4d3ee609416860429014877b695db878e04be7ca)
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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
42.Op Fl df
43.Op Fl t Ar termchar
44.Ar string
45.Op Ar file ...
46.Sh DESCRIPTION
47The
48.Nm
49utility displays any lines in
50.Ar file
51which contain
52.Ar string
53as a prefix.
54As
55.Nm
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
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
105.At v7 .
106