diff --git a/serial/serialutil.py b/serial/serialutil.py
index 5e1e490..150f5f2 100644
--- a/serial/serialutil.py
+++ b/serial/serialutil.py
@@ -570,6 +570,9 @@
     #  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -  -
     # additional functionality
 
+    def read_all(self):
+        return self.read(self.in_waiting)
+
     def read_until(self, terminator=LF, size=None):
         """\
         Read until a termination sequence is found ('\n' by default), the size