Update README for libnos's C libraries.
Change-Id: Ie13196965a5b51e996d6a34ae5f1ee176dac3036
diff --git a/README.md b/README.md
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--- a/README.md
+++ b/README.md
@@ -16,3 +16,15 @@
`libnos` is a C++ library for communication with a Nugget device. It offers an
interface to manage a connection and exchange data and a generator for RPC stubs
based on service protos.
+
+## `libnos_datagram`
+
+`libnos_datagram` is a C library for exchanging datagrams with a Nugget device.
+This directory only contains the API of the library as the different platforms
+will need to implement it differently.
+
+## `libnos_transport`
+
+`libnos_transport` is a C library for communicating with a Nugget device via the
+transport API. This is built on top of the `libnos_datagram` library for
+exchanging datagrams.