1.
#include <sys/types.h>
#include <unistd.h>
#include <stdio.h>
int main()
{
pid_t pid;
pid = fork();
if(pid>0) {
while(1) {
printf(“this is father print,pid = %d\n”,getpid());
sleep(1);
}
}
else if(pid == 0) {
while(1) {
printf(“this is child print,pid = %d\n”,getpid());
sleep(1);
}
}
return 0;
}
#include <sys/types.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
int main()
{
pid_t pid;
int cnt = 0;
pid = vfork();
if(pid>0) {
while(1) {
printf(“this is father print,pid = %d\n”,getpid());
sleep(1);
printf(“cnt = %d\n”,cnt);
}
}
else if(pid == 0) {
while(1) {
printf(“this is child print,pid = %d\n”,getpid());
sleep(1);
cnt++;
if(cnt == 3) {
exit(-1);
}
}
}
return 0;
}