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POMemory corruption when using SIGALRM and timer
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copied!<p>Ok not really sure if it is memory corruption or just a bug in my code, but here is the description of the problem: Single threaded program registers a SIGALRM handler:</p> <pre><code>struct sigaction action; sigset_t blocked; sigfillset(&blocked); sigdelset(&blocked, SIGKILL); sigdelset(&blocked, SIGSTOP); action.sa_handler = &handler_function; action.sa_flags = SA_RESTART; action.sa_mask = blocked; // We are not interested in the previous action: if (sigaction(SIGALRM, &action, NULL) == -1) .... </code></pre> <p>handler_function is a simple function which calls a function of an object:</p> <pre><code>void handler_function() { some_object->tick(); } tick() { ++variable; } </code></pre> <p>Variable is of type long. my program has only one instance of some_object and only signal handler calls function tick and only tick function modifies variable. Other functions only read value of variable. Forgot to mention that I create a timer:</p> <pre><code>struct timeval interval; interval.tv_sec = 0; interval.tv_usec = (100000); struct itimerval timer; timer.it_interval = interval; timer.it_value = interval; if (setitimer(ITIMER_REAL, &timer, NULL) == -1) ... </code></pre> <p>so tick function is triggered 10 times per second. Now the problem is that intermittently i get other data members of object some_object corrupted, they are POD types(long), i.e. all of a sudden they contain random values. I've tried to isolate a problem in a small program, but to no avail. Any advise would be appreciated. thanks</p>

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