* etc/byobu/backend, usr/lib/byobu/include/common,

usr/lib/byobu/include/constants: LP: #937174
  - fix upgrades while within a running byobu-screen session

debian/changelog

@@ -13,6 +13,9 @@ byobu (5.13) unreleased; urgency=low
   * usr/lib/byobu/include/shutil: LP: #930656
     - support network interface detection on Mac OSX
     - untested by me, but sort of suggested by a user
+  * etc/byobu/backend, usr/lib/byobu/include/common,
+    usr/lib/byobu/include/constants: LP: #937174
+    - fix upgrades while within a running byobu-screen session
 
  -- Dustin Kirkland <kirkland@ubuntu.com>  Thu, 16 Feb 2012 23:58:36 -0600
 

etc/byobu/backend

@@ -1,4 +1,4 @@
 # BYOBU_BACKEND can currently be "screen" or "tmux"
 # Override this on a per-user basis by editing "$BYOBU_CONFIG_DIR/backend"
 # or by launching either "byobu-screen" or "byobu-tmux" instead of "byobu".
-BYOBU_BACKEND="tmux"
+#BYOBU_BACKEND="tmux"

usr/lib/byobu/include/common

@@ -31,15 +31,13 @@ if [ -z "${BYOBU_INCLUDED_LIBS}" ]; then
 			if [ -d "$BYOBU_CONFIG_DIR" ] && [ -r "$BYOBU_CONFIG_DIR/profile" ]; then
 				# Previous byobu configuration exists, default to screen
 				for i in screen tmux; do
-					command -v $i >/dev/null && BYOBU_BACKEND="$i"
-					break
+					command -v $i >/dev/null && BYOBU_BACKEND="$i" && break
 				done
 				unset i
 			else
 				# New byobu configuration, default to tmux
 				for i in tmux screen; do
-					command -v $i >/dev/null && BYOBU_BACKEND="$i"
-					break
+					command -v $i >/dev/null && BYOBU_BACKEND="$i" && break
 				done
 				unset i
 			fi

usr/lib/byobu/include/constants

@@ -87,7 +87,7 @@ case "$BYOBU_BACKEND" in
 		ESC=
 	;;
 	screen)
-		export BYOBU_BACKEND="screen"
+		export BYOBU_BACKEND
 		BYOBU_ARG_VERSION="-v"
 		ESC="\005"
 	;;