I discovered a very useful parameter in the Gnu version of the patch program: --dry-run. The problem I have is to apply a set of patches (for the Win4Lin-enabled kernel) to the latest SuSE kernel. Trouble is that the Win4Lin patches are for a slightly older kernel version, but I'm assuming that if applied properly they will still work. Looking at the patches and the sources I can tell that the problem is that the code has been displaced by several lines. So I need to apply the patches in a nondestructive way, find the mismatches, and correct them manually. The Unix standard version of patch provides no help with that -- but fortunately the Gnu version does. Perhaps this information will help someone else some day. Paul Abrahams