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+The read event demultiplexer
+
+    select(2) on Unix FDs
+        ...
+    Fill up AX.25 interface packet buffers
+        ...
+    Decode as many packets as possible on each interface
+        ...
+    Fill up buffers for pending caller reads, open new connections
+        ...
+    If:
+        * ax25_select() is called: Notify caller of I/O events
+
+        * ax25_read() is called: Provide caller access to requested
+          buffer region
+
+    Buffer may be discarded upon next ax25_read() event, but should not
+    be discarded after an ax25_select() necessarily.