Thanks for the responses. I have added code tags, sorry.
I had originally moved a copy of the directory I wanted to patch to a new location for testing purposes. I think I finally somewhat understand the -p option. I still was having trouble, so since all I wanted was a dry-run, I went to the original directory I made the patch from. This directory was five directories up from the one I wanted to patch.
dir=directory patch was made from
target=directory I wanted diff-ed
My patch has this header, and as do the following hunks, with various file names.
diff -Npru dir2/dir3/dir4/target/dir6/dir7/dir8/dir9/files
So if I run from within dir
patch --dry-run /dir2 > file.patch
It no longer fails, just a blinking cursor. I have waited over 45 mins, but no change
I am running the patch file from the same directory it was created from on the same file that was diffed. I don't think I need any -p for that, do I? I've tried -p1 as well. Shouldn't it say hunks successful or something, or am I a real dummy and it just takes FOREVER?
There are like 3500 changes. Maybe I am just not being patient enough?