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rand(3) [netbsd man page]

RAND(3) 						   BSD Library Functions Manual 						   RAND(3)

NAME
rand, srand, rand_r -- bad random number generator LIBRARY
Standard C Library (libc, -lc) 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 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. SEE ALSO
random(3), rnd(4) STANDARDS
The rand() and srand() functions conform to ANSI X3.159-1989 (``ANSI C89''). The rand_r() function conforms to IEEE Std 1003.1c-1995 (``POSIX.1''). BSD
June 4, 1993 BSD

Check Out this Related Man Page

RAND(3) 						   BSD Library Functions Manual 						   RAND(3)

NAME
rand, rand_r, srand, sranddev -- bad random number generator LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <stdlib.h> int rand(void); int rand_r(unsigned *seed); void srand(unsigned seed); void sranddev(void); DESCRIPTION
These interfaces are obsoleted by arc4random(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. 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 seed must be supplied by the caller. SEE ALSO
arc4random(3), 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

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