Microsoft Knowledge Base Article
This article contents is Microsoft Copyrighted material.
©2005-©2007 Microsoft Corporation. All rights reserved.
Terms
of Use |
Trademarks
Article ID: 297826 - Last Review: October 16, 2002 - Revision: 1.1
FIX: CHRSAW() Function Can Cause System to Stop Responding When AutoYield = .F.
This article was previously published under Q297826
If the Visual FoxPro AutoYield property is set to .F., the
CHRSAW() function may not be able to check the keyboard buffer properly, and may cause the system to stop responding (hang).
The AutoYield property prevents Windows event messages from interrupting program flow. Therefore, when
CHRSAW() checks to see whether any keyboard events have come in, it can get into a state in which it continues to look for an event, but can't find one.
This problem was corrected in Microsoft Visual FoxPro version 7.0 for Windows.
Steps to Reproduce Behavior
The following code will eventually reproduce the behavior, although perhaps not on the first run. If you open the Task Manager, you will see that Visual FoxPro is taking all available CPU time.
*!* Q297826 FIX: CHRSAW() Function Can Hang System When AutoYield = .F.
CLEAR
_VFP.AutoYield = .F.
lnCount = 1000
lnStart = SECONDS()
FOR lnI = 1 TO lnCount
@ 1,1 SAY lnI
llTest = CHRSAW()
ENDFOR
? SECONDS() - lnStart
APPLIES TO
- Microsoft Visual FoxPro 5.0 Standard Edition
- Microsoft Visual FoxPro 5.0a
- Microsoft Visual FoxPro 6.0 Professional Edition
| kbbug kbcodesnippet kbfix kbvfp700fix KB297826 |
Community Feedback System
Very often, it takes hours to solve a problem. Very often, you've looked high
and low, and have tried a lot of solutions. When you finally found it, chances
are, it was because someone else helped you. Here's your chance to give back.
Use our community feedback tool to let others know what worked for you and what
didn't.
Please also understand that the community feedback system is not warranted to be
correct, it's simply a system that we've built to let people try and help each
other. If something in a feedback response doesn't make sense to you, or you're
not comfortable making changes that the feedback talks about (like registry
edits), please consult a professional.
Thank you for using kbAlertz.com Feedback System.
-- Scott Cate
Be the first to leave feedback, to help others about this knowledge base
article.
(Optional) Name
(Optional)
Public URL Or Email
Comments
No
HTML -- Text Only Please