In Ubuntu (Gnome) there is absolutely no way the change the mouse wheel scroll rate for GTK applications. It is hard-coded in GTK and determined by a "smart" algorithm which dynamically depends on the window size.
So I downloaded the source and found the function that returns the step value. I changed it to return a very small number first, and then 0 (to see if it has any affect at all).
I did
./configure
make
sudo make install
as instructed by GTK website.
It compiles with no problems (I have the libraries)
Bu then, I restart and it has absolutely no affect. My guess is Ubuntu is still using the original GTK it shipped with. What do you think is wrong here?
You should consider using the debian/ubuntu way of building from source as this ensures that all files goes to the intended directories. Running './configure' without any options usually sets PREFIX to '/usr/local'. Thus all the previous gtk files are still in place as they most likely reside in '/usr' and therefor gets loaded instead of the new ones you have compiled.
Try
apt-get source <package>
then modify the source to your liking.Then to build the package do
dpkg-build -rfakeroot -uc -b
to build a .deb. Then install the .deb with dpkg -i .This will replace the current install of the package rebuilt.
However the apt tools will try to replace this package at every system update. But it's a good way to try out changes.