Thanks for the patch, and sorry for the delayed reply. My concerns are: 1. Changing the meaning of the --libdir option so that it adds rather than replaces. We have no way of knowing if existing projects rely on that, but it's quite possible. A new option name is needed to avoid breaking compatibility. Since you don't like --libdirs (neither do I), maybe --add-libdir. (The new --print-libdir[s] is ok, since that won't change existing behavior, i.e., if the new "libdir list" functionality is not used, the output will be the same. As I understand it.)
2. Although Automake does not use the find_file function, autom4te (in autoconf) does. Right now the Automake and Autom4te FileUtils.pm are kept in sync (by make fetch in autoconf), as far as I can see. Thus we cannot change the behavior of find_file. Instead, a new function name is needed, e.g., find_file_no_cwd or find_file_with_opt. 2a. Also, the new description in the FileUtils.pm change does not mention the new final argument, or what the possible options can be. (I can tell from the code, I think, but it should be in the comment for the function.) 3. In order to install any patch, I need to ask you to sign a copyright disclaimer or assignment. I hope that's ok. I'll send you that form separately. Thanks again, Karl