summaryrefslogtreecommitdiffstats
path: root/src/extensions/README.md
diff options
context:
space:
mode:
Diffstat (limited to 'src/extensions/README.md')
-rw-r--r--src/extensions/README.md18
1 files changed, 12 insertions, 6 deletions
diff --git a/src/extensions/README.md b/src/extensions/README.md
index f75e0f236..8024ffa80 100644
--- a/src/extensions/README.md
+++ b/src/extensions/README.md
@@ -3,12 +3,10 @@
The protocol extensions in this folder are considered implementation details of
Qt. I.e. they may removed, renamed or changed without warning.
-## Suffixed protocols
-
-For protocols that have a version suffix, however, we will strive to not break
-backwards compatibility without bumping the suffix (renaming the protocol).
-E.g.: If your client sees a `zqt_key_v1` global, it can safely bind to it:
-the key event will always take the same number of arguments, regardless of
+However, starting with Qt 5.4, we promise not to break backwards compatibility
+without renaming (or removing) the protocol. I.e., if your client sees a global
+from one of these extensions, it can safely bind to it: the existing events
+and requests will always take the same number of arguments, regardless of
compositor version.
This is important also within a Qt-only scope if there are multiple versions of
@@ -16,3 +14,11 @@ Qt on the system. Consider for instance an application statically linked to Qt
(such as Qt Creator) running against a Qt compositor installed by the distro).
In such cases we don't want the compositor and client to disagree on the
protocol definition.
+
+## Protocol versioning.
+
+Protocol extensions in this folder should be versioned (e.g. `zqt_key_v1`).
+If it is necessary to break protocol compatibility, they will be renamed by
+incrementing the version number. For legacy reasons, there are also unversioned
+protocols in this folder. Those protocols should be renamed to be versioned
+if compatibility is broken.