Merge pull request #3103 from AndrzejKurek/ssl-read-improve-ret-code-doc
ssl - improve documentation on mbedtls_ssl_read and PEER_CLOSE_NOTIFY
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index b3c5288..136d7e6 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -3739,7 +3739,14 @@
*
* \return The (positive) number of bytes read if successful.
* \return \c 0 if the read end of the underlying transport was closed
- * - in this case you must stop using the context (see below).
+ * without sending a CloseNotify beforehand, which might happen
+ * because of various reasons (internal error of an underlying
+ * stack, non-conformant peer not sending a CloseNotify and
+ * such) - in this case you must stop using the context
+ * (see below).
+ * \return #MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY if the underlying
+ * transport is still functional, but the peer has
+ * acknowledged to not send anything anymore.
* \return #MBEDTLS_ERR_SSL_WANT_READ or #MBEDTLS_ERR_SSL_WANT_WRITE
* if the handshake is incomplete and waiting for data to
* be available for reading from or writing to the underlying
