Does any of you know how to get the pathname of the perl script that is being executed?

Say it is located in /home/wolfpack/perl/
I run it from /home/wolfpack by giving the absolute path name like,

/home/wolfpack/perl/scriptname [arguments]

I want to get the path /home/wolfpack/perl so that I can use some files inside that directory so that perl does not search for them inside the current working directory which is /home/wolfpack/

I just read about $0 in the Llama book. I think I can do something with it.