[aplorbust]

"patch will attempt to determine the type of the diff listing, unless over-ruled by a -c, -e, -n, or -u option.Context diffs (old-style, new- style, and unified) and normal diffs are applied directly by the patch program itself, whereas ed diffs are simply fed to the ed(1) editor via a pipe."

According to this, context diffs are not sent to ed.

Is the author suggesting that patch can be fooled to interpret a context diff as an ed diff?

Theres a file called pch.c with an excessive amount of parsing and "intuit" functions like intuit_diff_type().

patch has anthromorphised progress and error messages and tries to "guess".

However I am only a dumb end user. I should not question what I do not understand. Its all safe I'm sure.