Used this week when trying to debug a problem with an application that was resulting in errors that said “too many files open”:
/usr/sbin/lsof -p $processID | grep .$ext | wc -l
where $processID is the ID of the process that is opening the files and $ext is the (most likely) three letter file extension of the file that is being open.
Also, if you run:
and you get ‘unlimited’ as the result, you’d be wrong to assume that you have an unlimited number of file handles available to you:
will give you the total number of file handles you’re allowed.
And that’s one to grow on.