4.4BSD/usr/src/usr.bin/strings/strings.1

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.\"     @(#)strings.1	8.1 (Berkeley) 6/6/93
.\"
.Dd June 6, 1993
.Dt STRINGS 1
.Os BSD 3
.Sh NAME
.Nm strings
.Nd find printable strings in a file
.Sh SYNOPSIS
.Nm strings
.Op Fl afo
.Op Fl n Ar number
.Op Ar file ...
.Sh DESCRIPTION
.Nm Strings
displays the sequences of printable characters in each of the specified
files, or in the standard input, by default.
By default, a sequence must be at least four characters in length
before being displayed.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl a
By default,
.Nm strings
only searches the text and data segments of object files.
The
.Fl a
option causes
.Nm strings
to search the entire object file.
.It Fl f
Each string is preceded by the name of the file
in which it was found.
.It Fl n
Specifies the minimum number of characters in a sequence to be
.Ar number ,
instead of four.
.It Fl o
Each string is preceded by its decimal offset in the
file.
.El
.Pp
.Nm Strings
is useful for identifying random binaries, among other things.
.Sh SEE ALSO
.Xr hexdump 1
.Sh BUGS
The algorithm for identifying strings is extremely primitive.
In particular, machine code instructions on certain architectures
can resemble sequences of ASCII bytes, which
will fool the algorithm.
.Sh COMPATIBILITY
Historic implementations of
.Nm
only search the initialized data portion of the object file.
This was reasonable as strings were normally stored there.
Given new compiler technology which installs strings in the 
text portion of the object file, the default behavior was
changed.
.Sh HISTORY
The
.Nm
command appeared in
.Bx 3.0 .