process

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

int main() {
    // fork creates a child process.
    pid_t child = fork();
    if(child < 0) {
        printf("Error forking!\n");
        return 0;
    }
    // if the value of child pid is equal to 0 then we're in the child process
    else if(child == 0) {
        printf("Hello from the child (PID=%d)\n", getpid());
        exit(0);
    }
    // Waits until the child finishes.
    wait(NULL);
    printf("Parent(PID=%d) exiting...\n", getpid());
    return 0;
}