signals

My code in the main.m file is as follows. I haven't changed it at all from when I started programming this app. #import <UIKit/UIKit.h> #import "rickAppDelegate.h" int main(int argc, char *argv[]) { @autoreleasepool { return UIApplicationMain(argc, argv, nil, NSStringFromClass([rickAppDelegate class])); } } I am getting the SIGABRT error on the 'return UIApplicationMain' line. My program is an app which displays a red button and when you press it, it plays a video. This error appeared after I implemented iAds using this tutorial: http://www.ioslearner.com/implement-iads-tutorial-iphone-ipad

I just found out that someone is calling - from a signal handler - a definitely not async-signal-safe function that I wrote. So, now I'm curious: how to circumvent this situation from happening again? I'd like to be able to easily determine if my code is running in signal handler context (language is C, but wouldn't the solution apply to any language?): int myfunc( void ) { if( in_signal_handler_context() ) { return(-1) } // rest of function goes here return( 0 ); } This is under Linux. Hope this isn't an easy answer, or else I'll feel like an idiot. Apparently, newer Linux/x86 (probably since

Why does this problem occur? public static String path; private VideoView mVideoView; mVideoView = (VideoView) findViewById(R.id.surface_view); mVideoView.setVideoPath(path); mVideoView.setMediaController(new MediaController(this)); mVideoView.requestFocus(); //... private int mLayout = VideoView.VIDEO_LAYOUT_ZOOM; @Override public void onConfigurationChanged(Configuration newConfig) { if (mVideoView != null) mVideoView.setVideoLayout(mLayout, 0); super.onConfigurationChanged(newConfig); } The error message you are seeing is caused by dereferencing a null pointer in native code. From what you

I felt at peace with Posix after many years of experience. Then I read this message from Linus Torvalds, circa 2002: int ret; do { ret = close(fd); } while(ret == -1 && errno != EBADF); NO. The above is (a) not portable (b) not current practice The "not portable" part comes from the fact that (as somebody pointed out), a threaded environment in which the kernel does close the FD on errors, the FD may have been validly re-used (by the kernel) for some other thread, and closing the FD a second time is a BUG. Not only is looping until EBADF unportable, but any loop is, due to a race condition

I want to implement a "process wrapper" in Go. Basically what it will do, is launch a process (lets say a node server) and monitor it (catch signals like SIGKILL, SIGTERM ...) I think the way to do is to launch the node server in a go routine using syscall.Exec : func launchCmd(path string, args []string) { err := syscall.Exec(path, args, os.Environ()) if err != nil { panic(err) } } Then I'd like to catch every possible signals generated by the command executed by syscall . I'm pretty new to Go, any help would be appreciated. Luke There are three ways of executing a program in Go: syscall

Could anyone please explain in a really easy way to understand what sigemptyset() does? Why is it useful? I've read a bunch of definitions but i just don't understand. From what i gather it tracks the signals that are being used for blocking purposes? I'm not really sure i understand why that would be useful. Is it so we do not get that specific signal recursively? Basic example where sigemptyset() is used: #include <signal.h> #include <stdio.h> #include <unistd.h> int main(){ struct sigaction act; sigemptyset(&act.sa_mask); act.sa_handler=function_name; act.sa_flags=0; sigaction(SIGINT, &act,

I have the following piece of code in thread A, which blocks using pthread_cond_wait() pthread_mutex_lock(&my_lock); if ( false == testCondition ) pthread_cond_wait(&my_wait,&my_lock); pthread_mutex_unlock(&my_lock); I have the following piece of code in thread B, which signals thread A pthread_mutex_lock(&my_lock); testCondition = true; pthread_cond_signal(&my_wait); pthread_mutex_unlock(&my_lock); Provided there are no other threads, would it make any difference if pthread_cond_signal(&my_wait) is moved out of the critical section block as shown below ? pthread_mutex_lock(&my_lock);