System Workbench for STM32

So does the build number just get stored in the .h file, so it could be edited there?

I tried adding this to my project. Initially there was an issue because the editor converted the tabs to spaces. I fixed that and have copied your sample code verbatim, but I am getting an error:

make all 
if [ ! -r ../build.number ]; then \
			echo build_number=1 > ../build.number; \
		fi
! was unexpected at this time.
make: *** [../build.number] Error 255