doc update

diff --git a/doc/cha-gtls-app.texi b/doc/cha-gtls-app.texi
index 8b96ec7c5e44b6c5a5b216c58c8aa90b79dad0a0..0a4bbf2bc21cbabc51f15302427f50e4844d1d8e 100644 (file)
--- a/doc/cha-gtls-app.texi
+++ b/doc/cha-gtls-app.texi
@@ -145,6 +145,10 @@ verbose information on the @acronym{GnuTLS} functions internal flow.
 
 @showfuncB{gnutls_global_set_log_level,gnutls_global_set_log_function}
 
+Alternatively the environment variable @code{GNUTLS_DEBUG_LEVEL} can be
+set to a logging level and GnuTLS will output debugging output to standard
+error.
+
 When debugging is not required, important issues, such as detected
 attacks on the protocol still need to be logged. This is provided
 by the logging function set by