xref: /netbsd/lib/libc/string/strdup.3 (revision c4a72b64)
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32.\"     from: @(#)strdup.3	8.1 (Berkeley) 6/9/93
33.\"	$NetBSD: strdup.3,v 1.10 2002/08/11 07:53:06 yamt Exp $
34.\"
35.Dd August 11, 2002
36.Dt STRDUP 3
37.Os
38.Sh NAME
39.Nm strdup
40.Nd save a copy of a string
41.Sh LIBRARY
42.Lb libc
43.Sh SYNOPSIS
44.Fd #include \*[Lt]string.h\*[Gt]
45.Ft char *
46.Fn strdup "const char *str"
47.Sh DESCRIPTION
48The
49.Fn strdup
50function
51allocates sufficient memory for a copy
52of the string
53.Fa str ,
54does the copy, and returns a pointer to it.
55The pointer may subsequently be used as an
56argument to the function
57.Xr free 3 .
58.Pp
59If insufficient memory is available, NULL is returned.
60.Sh EXAMPLES
61The following will point
62.Va p
63to an allocated area of memory containing the null-terminated string
64.Qq foobar :
65.Bd -literal -offset indent
66char *p;
67
68if ((p = strdup("foobar")) == NULL) {
69	fprintf(stderr, "Out of memory.\en");
70	exit(1);
71}
72.Ed
73.Sh ERRORS
74The
75.Fn strdup
76function may fail and set the external variable
77.Va errno
78for any of the errors specified for the library function
79.Xr malloc 3 .
80.Sh SEE ALSO
81.Xr free 3 ,
82.Xr malloc 3 ,
83.Xr strcpy 3 ,
84.Xr strlen 3
85.Sh HISTORY
86The
87.Fn strdup
88function first appeared in
89.Bx 4.4 .
90