I want to write a program, that should be notified by O.S. whenever any running process on that OS dies.
I don't want to myself poll and compare everytime if a previously existing process has died. I want my program to be alerted by OS whenever a process termination happens.
How do I go about it? Some sample code would be very helpful.
PS: Looking for approaches in Java/C++.
Sounds like you want PsSetCreateProcessNotifyRoutine(). See this article to get started:
http://www.codeproject.com/KB/threads/procmon.aspx
Under Unix, you could use the sigchld signal to get notified of the death of the process. This requires, however, that the process being monitored is a child process of the monitoring process.
Under Windows, you might need to have a valid handle to the process. If you spawn the process yourself using CreateProcess, you get the handle for free, otherwise you must acquire by other means. It might then be possible to wait for the process to terminate by calling WaitForSingleObject on the handle.
Sorry, I don't have any example code for this. I am not even sure, that waiting on the process handle under Windows really awaits termination of the process (as opposed to some other "significant" condition, which causes the process handle to enter "signalled" state or something).
