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RAND(3)			 BSD 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 se-
     quence of pseudo-random numbers to	be returned by rand().	These se-
     quences 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.  However,	the rand()
     function still remains unsuitable for cryptographic use.

     The rand_r() function 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.

BSD				 May 25, 1999				   BSD

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | SEE ALSO | STANDARDS

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