Problem recompiling using make command in ubuntu

Question

I m trying to modify some C++ files in ns2 and then recompile using make command. Although new .o file is created after make, the output is similar to that of previous C++ file (before modifying). can someone suggest what may be the reason behind it.

Answer 1

Make sure you're running your newly built ns2 executable -- if you just type ns2, you'll get the installed ns2 binary on the system, which you haven't changed (unless you do a make install and even then it might install it in a different place, leaving the old one where it is).

Generally you'll need to run ./ns2 if you want to make sure you get the executable in the current directory (which is probably the one you just built, but check the Makefile and the date on the executable to be more sure.)