在POSIX上产生随机双精度的最好方法是什么？

#include <stdio.h>
#include <stdlib.h>

int main() {
    double random_double = drand48();
    printf("Random double: %f\n", random_double);
    return 0;
}

#include <stdio.h>
#include <stdlib.h>

int main() {
    long random_long = random();
    double random_double = (double)random_long / RAND_MAX;
    printf("Random double: %f\n", random_double);
    return 0;
}

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

int main() {
    srand48(time(NULL)); // 使用当前时间作为种子
    double random_double = drand48();
    printf("Random double: %f\n", random_double);
    return 0;
}

#include <stdio.h>
#include <stdlib.h>

int main() {
    long random_long = random();
    double random_double = (double)random_long / RAND_MAX * (upper_bound - lower_bound) + lower_bound;
    printf("Random double: %f\n", random_double);
    return 0;
}