Update MANUAL.txt for new filter behavior.

1 files changed, 17 insertions, 6 deletions

diff --git a/MANUAL.txt b/MANUAL.txt
index 763935c03..0b8681f04 100644
--- a/MANUAL.txt
+++ b/MANUAL.txt
@@ -421,12 +421,23 @@ Reader options
     exports `toJSONFilter` to facilitate writing filters in Haskell.
     Those who would prefer to write filters in python can use the
     module [`pandocfilters`], installable from PyPI. There are also
-    pandoc filter libraries in [PHP], [perl], and [javascript/node.js].
-
-    Note that the *EXECUTABLE* will be sought in the user's
-    `PATH`, and not in the working directory, if no directory is
-    provided.  If you want to run a script in the working directory,
-    preface the filename with `./`.
+    pandoc filter libraries in [PHP], [perl], and
+    [javascript/node.js].
+
+    If no directory is provided pandoc will look for executable or
+    non-executable filters in the director `$DATADIR/filters`, and
+    then for executable filters in the user's `PATH`. If you want to
+    run a script in the working directory, preface the filename with
+    `./`.
+
+    In order of preference, pandoc will look for filters in
+
+     1. a specified full or relative path (executable or
+     non-executable)
+     
+     2. `$DATADIR/filters` (executable or non-executable)
+     
+     3. `$PATH` (executable only)
 
 `-M` *KEY*[`=`*VAL*], `--metadata=`*KEY*[`:`*VAL*]