zombie_process.c

// C program that illustrated the concept of a
// zombie process in operatins systems. A process
// which has terminated execution but still has an entry
// in the process table is called a zombie process. 

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

int main()
{
    // fork() creates child process identical to parent
    int pid = fork();

    // if pid is greater than 0 than it is parent process
    // if pid is 0 then it is child process
    // if pid is -ve , it means fork() failed to create child process

    // Parent process
    if (pid > 0)
        sleep(20);

    // Child process
    else {
        exit(0);
    }

    return 0;
}