not debugging low level sources

["Edward S. Peschko" <esp5@pge.com>]

hey all,

I did a google search, and never got a good answer to the following question: 

I want to debug C++ code, and don't want to step into stl_alloc.h, etc. I'd rather 
just step into *user* code - and given the number of layers in C++, I'm spending
an inordinate amount of time bouncing in and out of standard headers.

Is there a way to turn off, or otherwise disable, what gdb steps into? Something like:

(gdb) block <dir>

or 

(gdb) block function

or somesuch?

Thanks much for any and all answers..

Ed