clarify %f documentation

It's natural to expect %f to be an actual file on disk; help avoid that mistake. Signed-off-by: Joey Hess <joeyh@joeyh.name> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Joey Hess committed Jul 11, 2016 at 18:45 UTC 52db4b0467f157230d2746f10435d070ad859bae
1 file changed +5
Documentation/gitattributes.txt
+5
@@ -374,6 +374,11 @@ substitution. For example:
374 smudge = git-p4-filter --smudge %f
375 ------------------------
376
377 +Note that "%f" is the name of the path that is being worked on. Depending
378 +on the version that is being filtered, the corresponding file on disk may
379 +not exist, or may have different contents. So, smudge and clean commands
380 +should not try to access the file on disk, but only act as filters on the
381 +content provided to them on standard input.
382
383 Interaction between checkin/checkout attributes
384 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^