[bug-patch] patch fails to give notice that it is being ran in 'dry-run' mode at any level of verbosity.

[Mike Hodson]

Good day,

I belive that the console output of 'patch' when in 'dry-run' mode should actually notify of this and explicitly mention that no files will be written or modified.

I have been trying to debug why something was not patching, when being used as part of Gentoo's portage emerge process.   Portage never specified that --dry-run was being used in any normal output (only if I dug through the source or an environment log, or straced and looked at the execve() call) so I was under the impression patch was actually being ran normally, and that the .rej file was present in the directory as the output of patch stated. 

This obviously was not the case, as portage tries a --dry-run pass before the real pass to simply find errors.  Portage in its patch process redirects all of patch's output to a log file. Due to the bug in portage, the command it logs is not actually the one that is executed. As such, this log file never once mentioned a dry run.  

Due to this, I believe patch needs some mention that a dry run pass is being called. 

A bug is also being filed with Gentoo's Portage project to not obfuscate the dry-run from the logged commandline output.

A simple addition of a notice that patch is being run in 'dry-run' mode would be greatly appreciated. 

Thanks,

Mike