#include <stdio.h>
#include <sys/wait.h>
#include <unistd.h>
#include <errno.h>
int main() {
int id1 = fork();
int id2 = fork();
if (id1 == 0) {
if (id2 == 0) {
printf("process a\n");
} else {
printf("process b\n");
}
} else {
if (id2 == 0) {
printf("process c\n");
} else {
printf("parent process\n");
}
}
while (wait(NULL) != -1 || errno != ECHILD) {
printf("wait for child process to finish\n");
}
return 0;
}
/*
run:
process c
process a
process b
wait for child process to finish
parent process
wait for child process to finish
wait for child process to finish
*/