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RAND(3)		       FreeBSD Library Functions Manual		       RAND(3)

NAME
     rand, srand, sranddev, rand_r -- bad random number	generator

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <stdlib.h>

     void
     srand(unsigned seed);

     void
     sranddev(void);

     int
     rand(void);

     int
     rand_r(unsigned *ctx);

DESCRIPTION
     These interfaces are obsoleted by random(3).

     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 seed 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 functions are automatically seeded with
     a value of	1.

     The sranddev() function initializes a seed	using the random(4) random
     number device which returns good random numbers, suitable for crypto-
     graphic use.

     rand_r() provides the same	functionality as rand().  A pointer to the
     context value ctx must be supplied	by the caller.

SEE ALSO
     random(3),	random(4)

STANDARDS
     The rand()	and srand() functions conform to ISO/IEC 9899:1990
     (``ISO C90'').

     The rand_r() function is as proposed in the POSIX.4a Draft	#6 document.

FreeBSD	11.1			 May 25, 1999			  FreeBSD 11.1
NAME | LIBRARY | SYNOPSIS | DESCRIPTION | SEE ALSO | STANDARDS

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