I am wondering what the M4 preprocessor is. The man page says:
DESCRIPTION When fvwm executes the FvwmM4 module, FvwmM4 invokes the M4 pre-proces- sor on the file specified in its invocation, then FvwmM4 causes fvwm to execute the commands in the resulting file.
I have a lot of questions, so I’ll just rattle them off:
What does this do? Is it enabled by default? If not, what are some good uses? How does it differ from the CPP preprocessor?
It seems like all that’s on google is a bunch of links to copies of the man page, so a good link or explanation would be great.