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RAND(3)                   OpenBSD Programmer's Manual                  RAND(3)

NAME
     rand, srand - bad random number generator

SYNOPSIS
     #include <stdlib.h>

     void
     srand(unsigned int seed);

     int
     rand(void);

     int
     rand_r(unsigned int *seed);

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 as the seed for a new sequence of
     pseudo-random numbers to be returned by rand().  These sequences are re-
     peatable 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 rand_r() is a thread-safe version of rand().  Storage for the seed
     must be provided through the seed argument, and needs to have been ini-
     tialized by the caller.

SEE ALSO
     arc4random(3), rand48(3), random(3)

STANDARDS
     The rand() and srand() functions conform to ANSI X3.159-1989 (``ANSI
     C'').

     The rand_r() function conforms to ISO/IEC 9945-1 ANSI/IEEE (``POSIX'')
     Std 1003.1c Draft 10.

OpenBSD 3.4                      June 29, 1991                               1

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | STANDARDS

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