8a486717_RPM_package_pt___FedoraProject__Action
[Stage] %prep [Reads] %_sourcedir [Writes] %_builddir [Action] 
This reads the sources and patches in the source directory %_sourcedir (usually ~/rpmbuild/SOURCES). It unpackages the sources to a subdirectory underneath the build directory %_builddir (usually ~/rpmbuild/BUILD/) and applies the patches.
How to create an RPM package/pt - FedoraProject