exit

/*
 *  call-seq:
 *     exit(integer=0)
 *     Kernel::exit(integer=0)
 *     Process::exit(integer=0)
 *  
 *  Initiates the termination of the Ruby script by raising the
 *  <code>SystemExit</code> exception. This exception may be caught. The
 *  optional parameter is used to return a status code to the invoking
 *  environment.
 *     
 *     begin
 *       exit
 *       puts "never get here"
 *     rescue SystemExit
 *       puts "rescued a SystemExit exception"
 *     end
 *     puts "after begin block"
 *     
 *  <em>produces:</em>
 *     
 *     rescued a SystemExit exception
 *     after begin block
 *     
 *  Just prior to termination, Ruby executes any <code>at_exit</code> functions
 *  (see Kernel::at_exit) and runs any object finalizers (see
 *  ObjectSpace::define_finalizer).
 *     
 *     at_exit { puts "at_exit function" }
 *     ObjectSpace.define_finalizer("string",  proc { puts "in finalizer" })
 *     exit
 *     
 *  <em>produces:</em>
 *     
 *     at_exit function
 *     in finalizer
 */

VALUE
rb_f_exit(argc, argv)
    int argc;
    VALUE *argv;
{
    VALUE status;
    int istatus;

    rb_secure(4);
    if (rb_scan_args(argc, argv, "01", &status) == 1) {
	switch (status) {
	  case Qtrue:
	    istatus = EXIT_SUCCESS;
	    break;
	  case Qfalse:
	    istatus = EXIT_FAILURE;
	    break;
	  default:
	    istatus = NUM2INT(status);
#if EXIT_SUCCESS != 0
	    if (istatus == 0) istatus = EXIT_SUCCESS;
#endif
	    break;
	}
    }
    else {
	istatus = EXIT_SUCCESS;
    }
    rb_exit(istatus);
    return Qnil;		/* not reached */
}