OpenBSD Programmer's Manual
NAME strdup, strndup — save a copy of a string
SYNOPSIS #include <string.h>
strdup(const char *s);
strndup(const char *s, size_t maxlen);
() function allocates sufficient memory for a copy of the string s
, does the copy, and returns a pointer to it. The pointer may subsequently be used as an argument to the function free(3)
The strndup() function behaves similarly to strdup but only copies up to maxlen characters from s. The resulting string is always NUL-terminated.
If insufficient memory is available, NULL is returned.
The following will point p
to an allocated area of memory containing the NUL-terminated string “foobar”:
p = strdup("foobar");
if (p == NULL)
() and strndup
() functions may fail and set the external variable errno
for any of the errors specified for the library function malloc(3)
STANDARDS The strdup() and strndup() functions conform to IEEE Std 1003.1-2008 (“POSIX.1”).
HISTORY The strdup() function first appeared in 4.3BSD-Reno. The strndup() function appeared in glibc 2.0, was reimplemented for NetBSD 4.0, and ported to OpenBSD 4.8.