Debugging running programs under linux can be extremely simple. The program
ltrace allows you to watch all the library calls being made which helps locate where a program is going wrong. It can also allow you to notice some basic performance bottlenecks.
-f flag is also particularly useful for watching a servers progress, and in particular a daemon that crashes. The typical method of initialisation for a daemon is to fork off, stop responding to various signals and then in the new process do the actual initialisation. If the daemon decides to terminate in the usual verbose unix fashion then you have a problem. Using the
-f flag means that
ltrace also monitors all the processes created by forking and allows you to see what actually caused it to finish.