[SOLVED] How to query the amount of free file handles from the OS?

[Hartmut]

I have the suspicion that my program does not close all files, which it opened, because after 18 days it stops doing it's job without cognizable reason. My program uses a foreign library which might be the causer.

I assume that Linux (in my case Ubuntu Server) can not open an endless amount of file handles at the same time.

Question1: is it possible to query, how many free file handles are currently left in Linux?

Question2: is it possible to query, how many file handles a certain program is currently occupying?

Thanks in advance.

[zeljko]

Goto /proc/YOURAPPPID and see how many files are open, or use lsof with pid param to see all relevant informations.

[Hartmut]

Thanks zeljko for your answer. I found out:

With "ls -l /proc/<PID>/fd" you can get a list of all opened file-handles of a PID.

With "lsof -p <PID>" you also can get a list of all opened file-handles of a PID.

[zeljko]

Also with ulimit you can increase number of opened file descriptors per process if needed

[Hartmut]

Thanks.