<directory>::
The repository to sync into.
-pre-receive Hook
+PRE-RECEIVE HOOK
----------------
Before any ref is updated, if $GIT_DIR/hooks/pre-receive file exists
and is executable, it will be invoked once with no parameters. The
hooks will not be invoked either. This can be useful to quickly
bail out if the update is not to be supported.
-update Hook
+See the notes on the quarantine environment below.
+
+UPDATE HOOK
-----------
Before each ref is updated, if $GIT_DIR/hooks/update file exists
and is executable, it is invoked once per ref, with three parameters:
As such it is not a good idea to send notices (e.g. email) from
this hook. Consider using the post-receive hook instead.
-post-receive Hook
+POST-RECEIVE HOOK
-----------------
After all refs were updated (or attempted to be updated), if any
ref update was successful, and if $GIT_DIR/hooks/post-receive
to evaluate it. It is recommended that hooks rely on sha1-new
rather than the current value of refname.
-post-update Hook
+POST-UPDATE HOOK
----------------
After all other processing, if at least one ref was updated, and
if $GIT_DIR/hooks/post-update file exists and is executable, then
exec git update-server-info
+QUARANTINE ENVIRONMENT
+----------------------
+
+When `receive-pack` takes in objects, they are placed into a temporary
+"quarantine" directory within the `$GIT_DIR/objects` directory and
+migrated into the main object store only after the `pre-receive` hook
+has completed. If the push fails before then, the temporary directory is
+removed entirely.
+
+This has a few user-visible effects and caveats:
+
+ 1. Pushes which fail due to problems with the incoming pack, missing
+ objects, or due to the `pre-receive` hook will not leave any
+ on-disk data. This is usually helpful to prevent repeated failed
+ pushes from filling up your disk, but can make debugging more
+ challenging.
+
+ 2. Any objects created by the `pre-receive` hook will be created in
+ the quarantine directory (and migrated only if it succeeds).
+
+ 3. The `pre-receive` hook MUST NOT update any refs to point to
+ quarantined objects. Other programs accessing the repository will
+ not be able to see the objects (and if the pre-receive hook fails,
+ those refs would become corrupted). For safety, any ref updates
+ from within `pre-receive` are automatically rejected.
+
+
SEE ALSO
--------
linkgit:git-send-pack[1], linkgit:gitnamespaces[7]