diff --git a/method/shell.py b/method/shell.py
index 2f5260b..f542fc7 100644
--- a/method/shell.py
+++ b/method/shell.py
@@ -84,7 +84,9 @@ class Pipe(Method):
         (prog, cmd, shell) = self._parse(w, **vargs)
         if prog is None or not cmd:
             return
+        self._dopipe(w, prog, cmd, shell)
 
+    def _dopipe(self, w, prog, cmd, shell):
         pipe = Popen(cmd, shell=shell, stdin=PIPE, stdout=PIPE, stderr=STDOUT)
         pid = pipe.pid
 
diff --git a/mode/awk.py b/mode/awk.py
index b435abb..be21b9c 100644
--- a/mode/awk.py
+++ b/mode/awk.py
@@ -80,7 +80,7 @@ class AwkFilterFile(Exec):
                        cmdname='awk', bufname='*Awk-Output*',
                        opts={'data': vargs['path']})
 
-class AwkFilterBuffer(Method):
+class AwkFilterBuffer(Pipe):
     pass
 class AwkFilterInput(Method):
     pass