introduce GIT_INDEX_VERSION environment variable

diff --git a/Documentation/technical/pack-protocol.txt b/Documentation/technical/pack-protocol.txt
index eb8edd1d4da4927f75e4ec0eaed5c8cce9ad0352..c73b62f5e1ced76d783dcd5e7aef64016ca1fb4c 100644 (file)
--- a/Documentation/technical/pack-protocol.txt
+++ b/Documentation/technical/pack-protocol.txt
@@ -464,7 +464,9 @@ contain all the objects that the server will need to complete the new
 references.
 
 ----
-  update-request    =  command-list [pack-file]
+  update-request    =  *shallow command-list [pack-file]
+
+  shallow           =  PKT-LINE("shallow" SP obj-id)
 
   command-list      =  PKT-LINE(command NUL capability-list LF)
                       *PKT-LINE(command LF)