I am writing gitosis post-push hook for central repository 
which pulls updates from central repository to testing enviroment
nano /var/git/repositories/holding.git/hooks/post-update
 #!/bin/bash
 cd /var/vh/holding;
 git reset --hard;
 git checkout testing;
 git pull;
here what I get after push on my client (development VM)
# blah ...
Counting objects: 57, done.
Compressing objects: 100% (24/24), done.
Writing objects: 100% (30/30), 3.42 KiB, done.
Total 30 (delta 18), reused 0 (delta 0)
fatal: Not a git repository: '.'
fatal: Not a git repository: '.'
fatal: Not a git repository: '.'
fatal: Not a git repository: '.'
To git@cheby.ru:holding.git
   233b5a2..0f46cd8  testing -> testing
Obviously, my attempt to tell git, where it should do pull, failed.
What is correct way to run git command for a specified working copy in bash script?