Hi, On Mon, Oct 13, 2003 at 10:06:36AM +0200, Gerhard Jaeger wrote: > thanks to Franz Bakan, I've managed to fix at least the sanei_thread support > for OS/2 - the test-backend works on that platform. > While searching through the backends, I noticed, that at least three other > backends (avision, mustek and hp) support OS/2 by defining a > os2_readerprocess. This is no longer necessary. (Peter Kirchgessner, had > already confirmed, that he will change his HP backend code...) > Please remove the os2_readerprocess and modify your code maybe that > way like it's done in the test backend. As soon, as every os2_readerprocess > function has disappeared, I will remove the porting stuff from sanei_thread.h.
I'm currently porting the mustek backend. While compilation and fork support (default) works on Linux using pthread doesn't work completely yet. I can scan but cancelling the scan freezes the application. I'm getting similar results with the test backend: Compile it with thread support and start a preview. There is a 10 second delay until the preview is finished. That's the delay at the end of the reader_process. But the reader_process should have benn immediately stopped by pthread_cancel(), shouldn't it? You have reduced the 1000 seconds to 10 seconds. The delay is there intentionally. In fact, the reader_process should never stop until it's killed by the main thread/process. The reason is that first the parent part of the pipe must be closed, not the child side. See SANE standard for sane_get_select_fd. So it would be even more correct to write something like "while (SANE_TRUE) sleep (1);" Maybe something is wrong with pthread_cancel()? Ok, the reason seems to be the blocking of all signals but sigterm in test.c. It works, if I don't do this. Maybe pthread_cancel() uses one of those signals? I guess we don't need to block the signals for the test backend. But at least for mustek, I need the signal blocking and the signal handler, otherwise the scanner may be left in a confused state if the scan is cancelled. Maybe I'll just block all siganls while reading/writing and enable all after that again. And the signal handler is called for all signals. Do you know which signal is used by pthread_cancel()? Bye, Henning
