Finally I used libzypp-bindings to get a MeeGo sysroot, but zypp.ZYppFactory_instance().getZYpp().commit(policy) did almost all the things including download and install, during this, not any info is showed, only a line info at last, we need to control download and installation, and give progresses, user should be able to interrupt it at any time using CTRL^C, but this is impossible currently, do