calling getenv() always returns NULL-pointer

Hello,

I would like to define an environment variable for reading back its value later in my c-code.

But getenv() always returns a NULL pointer, even if I try to read standard environment variables like "GCC_VERSION" or "PATH".

May be there are any additional settings (eclipse) or handling necessary, I'm not aware of?

Any idea or help, is very appreciated.

Thanks in advance and best regards

Ralph