I have an Oracle client 8.1.7 and I have installed the precompiler for Pro*C.
The problem is that it does not seem to work properly. I make the changes to a pro*C file and then try to precompile to the already existing c file using the graphical interface of the precompiler. The problem is that although it says that the precompilation has completed successfuly no changes are made to the c file. In the past a colleague could precompile the same files properly!