ultrix man page for exit

exit(3) 						     Library Functions Manual							   exit(3)

Name
       exit - terminate a process after flushing any pending output

Syntax
       void exit(status)
       int status;
       int atexit(func)
       void (*func)();

Description
       The  function  terminates  a process after calling the Standard I/O library function, _cleanup, to flush any buffered output.  The function
       never returns.

       The function registers a function to be called (without arguments) at normal program termination; functions are called in the reverse order
       of their registration (that is, most recent first). If a function is registered more than once, it will be called more than once.

Return Values
       The function returns zero if the registration succeeds, or -1 if the function pointer is null or if too many functions are registered.

See Also
       exit(2), intro(3s)

																	   exit(3)