[問題] 關於srand(time(NULL))應用於多process
#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<time.h>
int main(){
int n1=0,n2=0;
pid_t pid;
pid=fork();
if(pid==0){
srand(time(NULL));
//child
n1=rand()%10;
printf("n1:%d\n",n1);
exit(-1);
}//end if
else{
srand(time(NULL));
//parent
n2=rand()%10;
printf("n2:%d\n",n2);
wait();
}//end else
}//end main
上述code中，印出來的n1 以及 n2每次都相等
可是我就是希望他有時候不一樣，
回溯原因我想可能是出在srand(time(NULL))吧！
可是既然已經fork了
竟然發現兩個process的time(NULL)每次取的值都一樣
這是因為現在multi-processor的關係嗎？
想要讓兩個process time(NULL)取的值不同該怎麼做呢？
感謝大家~
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