用c语言编写程序,用fork

发布网友发布时间：2022-05-30 17:52

共1个回答

热心网友时间：2023-10-24 15:10

唉，这种题目也就是教科书，大体思路就是记录fork的返回值
如果是0，那就是子进程，如果大于零就是进程本身，然后嵌套条件语句
#include <stdio.h>
#include <unistd.h>

void show (char *name) {
printf ("PID:%5u %s\n", getppid(), getpid (), name);
sleep (30);
}

int main () {
pid_t c1 = fork ();
if (-1 == c1)
perror ("fail to create child 1");
else if (0 == c1) {
show ("child1");
}
else {
pid_t c2 = fork ();

if (-1 == c2)
perror ("fail to create child 2");
else if (0 == c2) {
pid_t g1 = fork ();

if (-1 == g1)
perror ("fail to create child of child 2");
else if (0 == g1) {
pid_t gg1 = fork ();

if (-1 == gg1)
perror ("fail to create grand-child of child 2");
else if (0 == gg1) {
show ("grand-child of child 2");
}
else {
show ("child of child 2");
}
}
else {
show ("child2");
}
}
else {
pid_t c3 = fork ();

if (-1 == c3)
perror ("fail to create child 3");
else if (0 == c3) {
show ("child3");
}
else
show ("main");
}
}
}