Hi, I need to modify an existing package which is built by OBS and I am looking for the easiest way to create patches for it. I know OBS packages are based on 1) .spec 2) source tar ball and 3) patches (for RPM format). And I can build it by "osc build ....". Questions about this "osc build". May I do incremental build? After I build the package first time, it provides me a folder /var/tmp/build-root, which contains the rootfs. May I just change the source code under /var/tmp/build-root/home/abuild/rpmbuild/BUILD/packages-xxx/file_name.c and then continue to build? I assume the 2nd build only build the modified files so it can finish as soon as possible. You know a large project takes long time to build. If I only need to change some small functions, I certainly don't want to build it from the beginning again. The incremental build will save me tons of debug hours. If this works, the patch creation process is like this 1) build package under OBS 2) modify source code 3) incremental build again (It even better, if I can go to chroot/qemu for the target env and build the package by run "configure" or "make") 4) generate patch and submit If osc does not support the incremental build, I guess the way to create patch is this, which involves 2 build system for one package. 1) build the package as how upstream do it 2) generate patch 3) test and submit the patch under OBS build. Regards, Dengyi Wang -- To unsubscribe, e-mail: opensuse-buildservice+unsubscribe@opensuse.org For additional commands, e-mail: opensuse-buildservice+help@opensuse.org