Re: [PyQt] Q(Core)Application.exec_() is not interruptable
Am Donnerstag, 1. Mai 2008 schrieb İsmail Dönmez: Following code can't be interrupted with CTRL-C : import sys from PyQt4.QtCore import QCoreApplication QCoreApplication.exec_(sys.argv) +1 on the question. I tried a lot like using module signal to trap a Ctrl+C but nothing seems to work. I guess the C++ port takes away keyboard events from Python. Any help appreciated. Christoph ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
Re: [PyQt] Q(Core)Application.exec_() is not interruptable
On Thu, 2008-05-01 at 20:24 +0200, Christoph Burgmer wrote: Am Donnerstag, 1. Mai 2008 schrieb İsmail Dönmez: Following code can't be interrupted with CTRL-C : import sys from PyQt4.QtCore import QCoreApplication QCoreApplication.exec_(sys.argv) +1 on the question. I tried a lot like using module signal to trap a Ctrl+C but nothing seems to work. I guess the C++ port takes away keyboard events from Python. Any help appreciated. CTRL+C causes a signal to be sent to the process. Python catches the signal, and sets a global variable, something like CTRL_C_PRESSED = True. Then, whenever the Python interpreter gets to execute a new opcode, it sees the variable set and raises a KeybordInterrupt. This means that CTRL+C works only if the Python interpreter is spinning. If the interpreter is executing an extension module written in C that executes a long-running operation, CTRL+C won't interrupt it, unless it explicitly cooperates with Python. Eg: time.sleep() is theoretically a blocking operation, but the implementation of that function cooperates with the Python interpreter to make CTRL+C work. This is all by design: CTRL+C is meant to do a clean abort; this is why it gets turned into an exception by Python (so that the cleanups are executed during stack unwind), and its support by extension modules is sort of opt-in. If you want to totally abort the process, without giving it a chance to cleanup, you can use CTRL+\. When Python calls QApplication::exec() (the C++ function), Qt doesn't know how to cooperate with Python for CTRL+C, and this is why it does not work. I don't think there's a good way to make it work; you may want to see if you can handle it through a global event filter. -- Giovanni Bajo Develer S.r.l. http://www.develer.com ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
Re: [PyQt] Q(Core)Application.exec_() is not interruptable
On Thursday 01 May 2008 14:28:31 İsmail Dönmez wrote: Following code can't be interrupted with CTRL-C : import sys from PyQt4.QtCore import QCoreApplication QCoreApplication.exec_(sys.argv) Is this somehow intended and is there a way to overcome this? You can catch the signal like this: import signal signal.signal(signal.SIGINT, signal.SIG_DFL) import sys from PyQt4.QtCore import QCoreApplication app = QCoreApplication(sys.argv) app.exec_() This is tested to work on linux, windows and osx. -- -- Ewald ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
Re: [PyQt] Q(Core)Application.exec_() is not interruptable
Hi, On Thu, May 1, 2008 at 10:54 PM, Ewald de Wit [EMAIL PROTECTED] wrote: On Thursday 01 May 2008 14:28:31 İsmail Dönmez wrote: Following code can't be interrupted with CTRL-C : import sys from PyQt4.QtCore import QCoreApplication QCoreApplication.exec_(sys.argv) Is this somehow intended and is there a way to overcome this? You can catch the signal like this: import signal signal.signal(signal.SIGINT, signal.SIG_DFL) import sys from PyQt4.QtCore import QCoreApplication app = QCoreApplication(sys.argv) app.exec_() That indeed works, thanks for the tip! -- Never learn by your mistakes, if you do you may never dare to try again. ___ PyQt mailing listPyQt@riverbankcomputing.com http://www.riverbankcomputing.com/mailman/listinfo/pyqt
