void
srand(unsigned int seed)
int
rand(void)
int
rand_r(unsigned int *seed)
The
rand()
function computes a sequence of pseudo-random integers in the range
of 0 to
RAND_MAX
(as defined by the header file
<stdlib.h>).
The
srand()
function sets its argument as the seed for a new sequence of
pseudo-random numbers to be returned by
rand().
These sequences are repeatable by calling
srand()
with the same seed value.
If no seed value is provided, the
rand()
function is automatically seeded with a value of 1.
The
rand_r()
function is a reentrant interface to
rand();
the seed has to be supplied and is maintained by the caller.
)
and
srand()
functions
conform to
ANSI X3.159-1989 (``ANSI C89'') .
The
rand_r()
function conforms to
IEEE Std 1003.1c-1995 (``POSIX.1'') .