signals

Let's say we have the follogin UI: +--------------------------+ |W1 +--------------+ | | |W2 | | | | +----------+ | | | | |W3 | | | | | +----------+ | | | | | | | +--------------+ | +--------------------------+ W3 is interested in a certain signal emited in W1 (or a level below, i.e. qApp). The idea is to develop W3 independently. But somebody has to do the signal/slot connection. What would be a good practice/recommended way of connecting the signal emited in W1 into slot in W3 if we want W3 not to know about any other widget, and we don't want W1 to know about W3 either? Solution 1: Connect

My system is ubuntu 12.04. I modify the example from man 2 signalfd , and add sigaddset(&mask, SIGSEGV) in the exmaple. But I can't get the output when SIGSEGV is generated. Is it a bug of glibc ? The fragment of source code is following: sigemptyset(&mask); sigaddset(&mask, SIGINT); sigaddset(&mask, SIGQUIT); sigaddset(&mask, SIGSEGV); /* Block signals so that they aren't handled according to their default dispositions */ if (sigprocmask(SIG_BLOCK, &mask, NULL) == -1) handle_error("sigprocmask"); sfd = signalfd(-1, &mask, 0); if (sfd == -1) handle_error("signalfd"); int* a = NULL; for (;;) {

I have a program that may have a lengthy execution. In the main module I have the following: import signal def run_program() ...time consuming execution... def Exit_gracefully(signal, frame): ... log exiting information ... ... close any open files ... sys.exit(0) if __name__ == '__main__': signal.signal(signal.SIGINT, Exit_gracefully) run_program() This works fine, but I'd like the possibility to pause execution upon catching SIGINT, prompting the user if they would really like to quit, and resuming where I left off in run_program() if they decide they don't want to quit. The only way I can

I have a program that creates many threads and runs until either power is shutdown to the embedded computer, or the user uses kill or ctrl c to terminate the process. Here's some code and how the main() looks. static int terminate = 0; // does this need to be volatile? static void sighandler(int signum) { terminate = 1; } int main() { signal(SIGINT, sighandler); // ... // create objects, spawn threads + allocate dynamic memory // ... while (!terminate) sleep(2); // ... // clean up memory, close threads, etc. // ... signal(SIGINT, SIG_DFL); // is this necessary? } I'm wondering a few things: Is

I have created a pthread, and installed a signal handler inside that, same way as we do in main( ) function. The thread's signal handler is a separate function. Surprisingly, it is not working, that is the thread's signal handler is not able to catch signals. Here is the code: #include <pthread.h> #include <unistd.h> #include <sys/types.h> #include <stdio.h> #include <signal.h> typedef struct data { char name[10]; int age; }data; void sig_func(int sig) { printf("Caught signal: %d\n",sig); signal(SIGSEGV,sig_func); } void func(data *p) { printf("This is from thread function\n"); signal(SIGSEGV

In my application, I want to create entries in certain tables when a new user signs up. For instance, I want to create a userprofile which will then reference their company and some other records for them. I implemented this with a post_save signal: def callback_create_profile(sender, **kwargs): # check if we are creating a new User if kwargs.get('created', True): user = kwargs.get('instance') company = Company.objects.create(name="My Company") employee = Employee.objects.create(company=company, name_first=user.first_name, name_last=user.last_name) profile = UserProfile.objects.create(user