How the fork() System Call Actually Works in Linux

The fork() System Call

pid_t pid = fork();
if (pid == 0) {
    printf("I am the child!\n");
} else {
    printf("I am the parent of %d!\n", pid);
}

⚡ Copy-on-Write (COW)

Rather than copying gigabytes of RAM during fork(), the kernel marks all page table entries as read-only. A page is physically cloned only when one process attempts to write to it.

Explore the full interactive process lifecycle on Binary Dose.