Update runtime files.
diff --git a/runtime/doc/quickfix.txt b/runtime/doc/quickfix.txt
index 7981439..b042063 100644
--- a/runtime/doc/quickfix.txt
+++ b/runtime/doc/quickfix.txt
@@ -1,4 +1,4 @@
-*quickfix.txt* For Vim version 7.4b. Last change: 2013 Mar 07
+*quickfix.txt* For Vim version 7.4b. Last change: 2013 Aug 03
VIM REFERENCE MANUAL by Bram Moolenaar
@@ -899,6 +899,8 @@
Special characters in 'errorformat' are comma and backslash. See
|efm-entries| for how to deal with them. Note that a literal "%" is matched
by "%%", thus it is not escaped with a backslash.
+Keep in mind that in the `:make` and `:grep` output all NUL characters are
+replaced with SOH (0x01).
Note: By default the difference between upper and lowercase is ignored. If
you want to match case, add "\C" to the pattern |/\C|.