Date: Tue, 4 May 1999 11:01:04 +0300 (IDT) From: Eli Zaretskii X-Sender: eliz AT is To: djgpp-workers AT delorie DOT com Subject: Timer ticks under Windows 9X Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Reply-To: djgpp-workers AT delorie DOT com Windows 9X doesn't cease to surprise me... I noticed that the timer tick interrupts (Int 8, IRQ0) are NOT delivered to a DOS box unless it has the focus. You can uncheck the "Background: Always suspend" option in the property sheets (which is what I did a long time ago), and then the program continues to run, but it doesn't get the timer interrupts! The effect of this is that `alarm' and `setitimer' (and probably profiling as well) all stop working when the program's window is in the background. A simple test program that defines a SIGALRM handler which increments a counter, and then prints the counter in its `main' function, will show you that the counter stops updating when the focus is taken away from the program's window. I will update the docs for the related library functions, but if somebody knows how to work around this ``feature'', I'd surely like to know.