NAME
	WaitIO -- wait for completion of an I/O request

   SYNOPSIS
	error = WaitIO(iORequest)
	D0	       A1

	BYTE WaitIO(struct IORequest *);

   FUNCTION
	This function waits for the specified I/O request to complete, then
	removes it from the replyport.	If the I/O has already completed,
	this function will return immediately.

	This function should be used with care, as it does not return until
	the I/O request completes; if the I/O never completes, this
	function will never return, and your task will hang.  If this
	situation is a possibility, it is safer to use the Wait() function.
	Wait() will return return when any of a specified set of signal is
	received.  This is how I/O timeouts can be properly handled.

   WARNING
	If this IORequest was "Quick" or otherwise finished BEFORE this
	call, this function drops though immediately, with no call to
	Wait().  A side effect is that the signal bit related the port may
	remain set.  Expect this.

	When removing a known complete IORequest from a port, WaitIO() is the
	preferred method.  A simple Remove() would require a Disable/Enable
	pair!

   INPUTS
	iORequest - pointer to an I/O request block

   RESULTS
	error - zero if successful, else an error is returned
		(a sign extended copy of io_Error).

   SEE ALSO
	DoIO(), SendIO(), CheckIO(), AbortIO()