numbered sequentially from 1, and uses the first line of the commit
message (massaged for pathname safety) as the filename.
-When -o is specified, output files are created in that directory; otherwise in
-the current working directory.
+There are three output modes. By default, output files are created in
+the current working directory; when -o is specified, they are created
+in that directory instead; when --stdout is specified, they are spit
+on standard output, and can be piped to git-am.
When -n is specified, instead of "[PATCH] Subject", the first line is formatted
as "[PATCH N/M] Subject", unless you have only one patch.