git-pull sets write bit, git-push does not

git-pull sets write bit, git-push does not

Hello,

Background: I am using Git locally with ClearCase upstream. I
initialized a Git repository on top of a ClearCase snapshot view,
while my work branches are in a clone. As ClearCase is particular
about the write bit, I have come to depend on an undocumented feature
of Git. Namely, that git-push preserves read only permissions, while
git-pull sets modified files writable.

Can git-push be relied upon to preserve the write bit (readonly)? Why is git-pull different? Is it a side effect of the plumbing?

Thanks, Alex

http://genaud.net/2008/08/clearcase-globally-git-locally/

Simplified case:

echo -- echo create a repo r1 with files A and B committed echo -- mkdir r1 cd r1 echo A > A echo B > B git init git add . git commit -m init

echo -- echo create an identical repo r2 whose files are readonly echo -- cp -r ../r1 ../r2 chmod u-w ../r2/[AB]

echo -- echo push a modification of A from r1 to r2 echo -- echo AA > A git commit -a -m modA git push ../r2

echo -- echo pull a modification of B from r1 to r2 echo -- echo BB > B git commit -a -m modB cd ../r2 git pull ../r1

echo -- echo notice that pushed A remains readonly echo while pulled B has become writable echo -- ls -l