git pull in a hook not executing

I have a system setup like this:

http://joemaller.com/990/a-web-focused-git-workflow/

However no matter how I configure the shell environment (i.e. GIT_DIR and PWD) the git-pull command does NOT run when called by the hook. Literally there is NO output whatsoever.

My post-update looks like:

#!/bin/sh    
/git/Lunch.git/lunch-receive > lunch.txt

and my lunch-receive script looks like:

#!/bin/sh
service myService stop
cd /usr/lunch
unset GIT_DIR
git reset --hard # necessary or the pull fails
git pull hub master # this line DOESN'T RUN grrrrr!
chmod u+x *.sh
chmod -R u+x bin
service开发者_开发技巧 myService start

Finally, lunch.txt (the output) looks like

HEAD is now at 5956c0b [old commit message]

Absurdly, changing

/git/Lunch.git/lunch-receive > lunch.txt

to:

/git/Lunch.git/lunch-receive > lunch.txt 2>&1

and

git pull hub master

to:

 echo before-pull
 git pull --verbose hub master || echo "git-pull: returned error code"
 echo after-pull

seemed to have fixed the problem