Git sends the content split in zero or more pkt-line packets and a
flush packet to terminate content. Please note, that the filter
must not send any response before it received the content and the
-final flush packet.
+final flush packet. Also note that the "value" of a "key=value" pair
+can contain the "=" character whereas the key would never contain
+that character.
------------------------
packet: git> command=smudge
packet: git> pathname=path/testfile.dat