xref: /386bsd/usr/src/usr.bin/strings/strings.1 (revision a2142627)
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32.\"     @(#)strings.1	6.11 (Berkeley) 5/9/91
33.\"
34.Dd May 9, 1991
35.Dt STRINGS 1
36.Os BSD 3
37.Sh NAME
38.Nm strings
39.Nd find printable strings in a file
40.Sh SYNOPSIS
41.Nm strings
42.Op Fl afo
43.Op Fl n Ar number
44.Op Ar file ...
45.Sh DESCRIPTION
46.Nm Strings
47displays the sequences of printable characters in each of the specified
48files, or in the standard input, by default.
49By default, a sequence must be at least four characters in length
50before being displayed.
51.Pp
52The options are as follows:
53.Bl -tag -width Ds
54.It Fl a
55By default,
56.Nm strings
57only searches the text and data segments of object files.
58The
59.Fl a
60option causes
61.Nm strings
62to search the entire object file.
63.It Fl f
64Each string is preceded by the name of the file
65in which it was found.
66.It Fl n
67Specifies the minimum number of characters in a sequence to be
68.Ar number ,
69instead of four.
70.It Fl o
71Each string is preceded by its decimal offset in the
72file.
73.El
74.Pp
75.Nm Strings
76is useful for identifying random binaries, among other things.
77.Sh SEE ALSO
78.Xr hexdump 1
79.Sh BUGS
80The algorithm for identifying strings is extremely primitive.
81In particular, machine code instructions on certain architectures
82can resemble sequences of ASCII bytes, which
83will fool the algorithm.
84.Sh COMPATIBILITY
85Historic implementations of
86.Nm
87only search the initialized data portion of the object file.
88This was reasonable as strings were normally stored there.
89Given new compiler technology which installs strings in the
90text portion of the object file, the default behavior was
91changed.
92.Sh HISTORY
93The
94.Nm
95command appeared in
96.Bx 3.0 .
97