[ns] how to compile a cc file???

[azee]

Hi guys!
I change something in ns-allinone-2.28\ns-2.28\mac\mac-802_11.cc file and
after saving it, I run the command make clean; make (I am using cygwin). The
change is just a print statement that should appear in the simulation
result.
After that, I run the tcl simulation code again, but the changes that I made
are not appearing in the result. Am I on the right track? How to chnage
things in cc files?
thanks for your help.
-azee