Geografic-Information-System/raster/r.random/creat_rand.c

#include <time.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <grass/config.h>


#ifndef USE_RAND

#ifndef HAVE_DRAND48
#define lrand48() (((long) rand() ^ ((long) rand() << 16)) & 0x7FFFFFFF)
#define srand48(sv) (srand((unsigned)(sv)))
#endif


long make_rand(void)
{
    return lrand48();
}

void init_rand(void)
{
    srand48((long)time((time_t *) 0));
}

#else

static long labs(int n)
{
    return n < 0 ? (-n) : n;
}

long make_rand(void)
{
    return (labs(rand() + (rand() << 16)));
}

void init_rand(void)
{
    srand(getpid());
}

#endif