Aren't those configure scripts generate by some other tool :)
Maybe. I never digged that deep into build processes. After some time I got myself to write Makefiles, but that's about it. I see names like automake, m4, configure etc. pop up now and then and have no idea what role each plays. They just get the job done somehow and check which C standard library is used, what compiler and other useful traits to cover the differences between systems.
