Code instance
#include <stdio.h> #include <unistd.h>/* program output results main process id:8377 process id:8377, parent process id:3290, episode process id:8377, parent process id:3290, Bye process id:8378, parent process Id:8377,hello process id:8378, parent process Id:8377,bye process id:8379, parent process id:1397, episode process id:8379, parent process Id:1397,bye process id:8380, Parent process Id:1397,hello Process id:8380, parent process Id:1397,bye*/int main () {printf ("main process id:%d\n", getpid ()); if (fork () ==0| | Fork () ==0&&fork () ==0) {printf ("process id:%d, parent process id:%d,hello\n", getpid (), Getppid ());} else {printf ("process id:%d, Parent process id:%d, episode \ n ", Getpid (), Getppid ());} printf ("Process id:%d, parent process id:%d,bye\n", getpid (), Getppid ()); return 0;}
Worth a bit of experience. Back post analysis.
An understanding case of the system parent process and the child process