fork() function.

NAME
       fork - create a child process

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

       pid_t fork(void);

 

RETURN VALUE
       On  success,  the  PID of the child process is returned in the parent, and 0 is returned in the child.  On failure, -1 is re‐turned in the parent, no child process is created, and errno is set appropriately.