1. C언어 Stack and Dynamic allocation test when using fork 2. C언어 보무프로세스 죽는 test

halmoni.c

#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>

int main()
{
     pid_t pid, pid2;
     if(  (pid = fork()) < 0  ) {
          perror("fork failed");
     } 
     else if( pid == 0 ) {
         printf("child process %d alive\n", getpid() );
  	if((pid2 = fork()) < 0) {
			perror("child fork failed");
		} else if(pid2 == 0) {
			printf("grandchild %d started\n", getpid());
          	sleep( 30 );
			printf("grandchild %d dying\n", getpid());
			exit(0);
		} else {
          printf("child process %d dying with 0\n", getpid() );
		  exit(0);
		}
     }
     else {
          printf("parent process : sleeping for 10\n" );
		sleep(30);
     }
	return 0;
}

memory_test.c

// C언어 Stack and Dynamic allocation test when using fork

#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>

int main()
{
     pid_t pid;
  int shared = 1;
	int *shared2 = malloc(sizeof(int) * 1000);
	shared2[999] = 37;
     if(  (pid = fork()) < 0  ) {
          perror("fork failed");
     } 
     else if( pid == 0 ) {
          sleep( 5 );
          printf("child process dying\n" );
		  printf("stack memory = %d\n", shared);
		  printf("malloc %p memory = %d\n", &shared2[999], shared2[999]);
          exit(0);
     }
     else {
		printf("before parent dies with %d and %d\n", shared, shared2[999]);
		shared = 5;
		shared2[999] = 42;
        printf("parent process dying\n" );
		printf("parent memory = %d\n", shared);
		printf("parent malloc %p memory = %d\n", &shared2[999], shared2[999]);
		exit(0);
     }
	return 0;
}