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.\"     @(#)strdup.3	8.1 (Berkeley) 6/9/93
.\"
.Dd June 9, 1993
.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 null-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 .