SNMP to many files open at ones

I am using SNMP in my project and when the server has been running for a while I get an error that I have to many files opened.

I have tried to read all kinds of forums and from my point of view I am closing the files everytime I read something using SNMP.

The code can be found at:

and the error message at:

Can someone find the error because I cannot!

Thanks in advance.