CLSID

OLERequestPendingTimeout, OLEServerBusyRaiseError, OLEServerBusyTimeout

Microsoft certainly wasn't miserly with the letters when naming these jawbreakers! They all have to do with how you manage delays and timeouts within your OLE Server application.

Usage

nPendingTimeout = oApp.OLERequestPendingTimeout oApp.OLERequestPendingTimeout = nPendingTimeout nBusyTimeout = oApp.OLEServerBusyTimeout oApp.OLEServerBusyTimeout = nBusyTimeout lRaiseError = oApp.OLEServerBusyRaiseError oApp.OLEServerBusyRaiseError = lRaiseError

Parameter	Value	Meaning
nPendingTimeout	Positive number	The amount of time in milliseconds to wait before displaying a message that the application is busy.
	Zero or negative	No message is displayed.
nBusyTimeout	Numeric	The amount of time to wait (in milliseconds) before raising an error if OLEServerBusyRaiseError is .T.
	Zero or negative	No error is raised.
lRaiseError	.T.	Create an error if an OLE request waits longer than the OLEServerBusyTimeout specified delay.
	.F.	Don't error if the request is not answered in time. Without an error message, your application appears to hang.

We find these settings a little confusing because their names don't make clear the differences between them. The Request setting dictates the response to a user request, like clicking on a button or form. The ServerBusy settings affect how VFP reacts if program code can't continue because a server is busy. Note, also, that both situations apply only if VFP is trying to work with a COM server in a separate process space—an EXE, not a DLL—and that you get no timeout errors if VFP is working with an in-process, DLL COM server.

OLERequestPendingTimeout is the amount of time delay after a mouse click or key is pressed before displaying "The action cannot be completed because the other program is busy. Choose 'Switch To' to activate the busy program and correct the problem." The default is 5 seconds. We think that failing to respond to a user request is a cardinal sin among UI no-no's, and we prefer to crank this down to 500 milliseconds or so.

OLEServerBusyTimeout and OLEServerBusyRaiseError work together to determine the behavior an application should take if a request to an OLE server is rejected because the server is busy. After the amount of time specified by the Timeout, VFP will raise an error if RaiseError is set to true, or not. This error is not in the form of a VFP error as we had hoped, nor an OLE error, but rather the same old "This action cannot be completed " dialog. We think that's lame. If we need to create a COM server and expect sub-five-second response time, we want the process to fail and let us know we can't get it. That would give VFP control and developers the chance to do something about it.

Example

_VFP.OLERequestPendingTimeout = 500  && half a second _VFP.OLEServerBusyTimeout = 5000     && five seconds _VFP.OLEServerBusyRaiseError = .T.   && let operator know

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Copyright © 2002 by Tamar E. Granor, Ted Roche, Doug Hennig, and Della Martin. All Rights Reserved.