Explain the Exit (status) Function 

Exit function causes the calling process to be terminated. Actually, all file descriptors are immediately closed but the process is   not removed from memory unless all references to it (shared memory, etc) are completed. The method is said to be a "zombie process" if there are outstanding references made after the exist is performed. If a parent process is waiting with a wait () system call, it is notified of the termination and receives the low-order 8 bits of status.