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CRTL, srand48
*Conan The Librarian
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Initializes a 48-bit random-number generator.
Format
#include <stdlib.h>
void srand48 (long int seed_val);
seed_val
The initialization value to begin randomization. Changing this
value changes the randomization pattern.
The srand48 function initializes the random-number generator. You
can use this function in your program before calling the drand48,
lrand48, or mrand48 functions. (Although it is not recommended
practice, constant default initializer values are automatically
supplied if you call drand48, lrand48, or mrand48 without calling
an initialization function).
The function works by generating a sequence of 48-bit integer
values, Xi, according to the linear congruential formula:
Xn+1 = (aXn+c)mod m n >= 0
The argument m equals 248, so 48-bit integer arithmetic is
performed. Unless you invoke the lcong48 function, the multiplier
value a and the addend value c are:
a = 5DEECE66D16 = 2736731631558
c = B16 = 138
The initializer function srand48 sets the high-order 32 bits
of Xi to the low-order 32 bits contained in its argument. The
low-order 16 bits of Xi are set to the arbitrary value 330E16.
See also drand48, lrand48, and mrand48.