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.\" $OpenBSD: strdup.3,v 1.14 2007/05/31 19:19:32 jmc Exp $
.\"
.\" Copyright (c) 1990, 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
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.\" modification, are permitted provided that the following conditions
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.\" 3. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\"
.\"     @(#)strdup.3	8.1 (Berkeley) 6/9/93
.\"
.Dd $Mdocdate: May 31 2007 $
.Dt STRDUP 3
.Os
.Sh NAME
.Nm strdup
.Nd save a copy of a string
.Sh SYNOPSIS
.Fd #include <string.h>
.Ft char *
.Fn strdup "const char *s"
.Sh DESCRIPTION
The
.Fn strdup
function allocates sufficient memory for a copy of the string
.Fa s ,
does the copy, and returns a pointer to it.
The pointer may subsequently be used as an argument to the function
.Xr free 3 .
.Pp
If insufficient memory is available,
.Dv NULL
is returned.
.Sh EXAMPLES
The following will point
.Va p
to an allocated area of memory containing the NUL-terminated string
.Qq foobar :
.Bd -literal -offset indent
char *p;

if ((p = strdup("foobar")) == NULL) {
	fprintf(stderr, "Out of memory.\en");
	exit(1);
}
.Ed
.Sh ERRORS
The
.Fn strdup
function may fail and set the external variable
.Va errno
for any of the errors specified for the library function
.Xr malloc 3 .
.Sh SEE ALSO
.Xr free 3 ,
.Xr malloc 3 ,
.Xr strcpy 3 ,
.Xr strlcpy 3 ,
.Xr strlen 3
.Sh HISTORY
The
.Fn strdup
function first appeared in
.Bx 4.4 .