single-instance

I have to restrict my .net 4 WPF application so that it can be run only once per machine. Note that I said per machine, not per session. I implemented single instance applications using a simple mutex until now, but unfortunately such a mutex is per session. Is there a way to create a machine wide mutex or is there any other solution to implement a single instance per machine application? I would do this with a global Mutex object that must be kept for the life of your application. MutexSecurity oMutexSecurity; //Set the security object oMutexSecurity = new MutexSecurity(); oMutexSecurity

I want to prevent multiple instances of application being launched in java. I know 2 methods for this: locking file locking socket But which is one is more efficient and good to use? Which one should I use? Any other solution to do the same are also welcome. EDIT: I tried that with Win200864b(version isn't important) and alive JFrame and move toFront() or Iconified in SystemTray with JFrame.DO_NOTHING_ON_CLOSE public interface ApplicationStartedListener { void applicationStarted(); void foreignApplicationStarted(String name); void messageArrived(Object obj); } // import java.io.Serializable;

I have an Activity which is basically my main activity and its launch mode is single instance. But because of singleInstance, the onActivityResult() callback does not fire. And if I change the launch mode in my manifest file to any other mode it works fine. Can you explain why this callback is not working? Pedro Loureiro I believe that the problem is that singleInstance doesn't let the callee activity to exist in the same task as the caller, hence it can't return the value to the caller. Consider using singleTask instead: singleTask The system creates the activity at the root of a new task and

What would be your suggestion in order to create a single instance application, so that only one process is allowed to run at a time? File lock, mutex or what? Maxim Egorushkin A good way is: #include <sys/file.h> #include <errno.h> int pid_file = open("/var/run/whatever.pid", O_CREAT | O_RDWR, 0666); int rc = flock(pid_file, LOCK_EX | LOCK_NB); if(rc) { if(EWOULDBLOCK == errno) ; // another instance is running } else { // this is the first instance } Note that locking allows you to ignore stale pid files (i.e. you don't have to delete them). When the application terminates for any reason the