I have set up cgminer on a linux machine to mine litecoins. I already installed the nvidia driver for this. Yesterday at night I put it to mine (I guess) but I'm in doubt if it is really mining because the hashes per time is still zero as in the picture. How to know if it is actually minining or not?
CGMiner no longer has support for GPU or CPU mining at all. You are currently not mining anything. In order to do GPU mining, you will need to either compile it yourself to support GPU mining or get an ASIC or get an older version of CGMiner that supports GPU mining or find a fork of it that supports GPU mining.