xref: /openbsd/lib/libc/string/strdup.3 (revision db3296cf)
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30.\"     @(#)strdup.3	8.1 (Berkeley) 6/9/93
31.\"
32.Dd June 9, 1993
33.Dt STRDUP 3
34.Os
35.Sh NAME
36.Nm strdup
37.Nd save a copy of a string
38.Sh SYNOPSIS
39.Fd #include <string.h>
40.Ft char *
41.Fn strdup "const char *s"
42.Sh DESCRIPTION
43The
44.Fn strdup
45function allocates sufficient memory for a copy of the string
46.Fa s ,
47does the copy, and returns a pointer to it.
48The pointer may subsequently be used as an argument to the function
49.Xr free 3 .
50.Pp
51If insufficient memory is available,
52.Dv NULL
53is returned.
54.Sh EXAMPLES
55The following will point
56.Va p
57to an allocated area of memory containing the null-terminated string
58.Qq foobar :
59.Bd -literal -offset indent
60char *p;
61
62if ((p = strdup("foobar")) == NULL) {
63	fprintf(stderr, "Out of memory.\en");
64	exit(1);
65}
66.Ed
67.Sh ERRORS
68The
69.Fn strdup
70function may fail and set the external variable
71.Va errno
72for any of the errors specified for the library function
73.Xr malloc 3 .
74.Sh SEE ALSO
75.Xr free 3 ,
76.Xr malloc 3 ,
77.Xr strcpy 3 ,
78.Xr strlcpy 3 ,
79.Xr strlen 3
80.Sh HISTORY
81The
82.Fn strdup
83function first appeared in
84.Bx 4.4 .
85