query for package updates

[Reza Alizadeh Majd]

Hi, 

I'm working on a cron job to perform `guix pull` periodically and inform users
about available updates. previously it was suggested to use `guix package -u -n`
to find if any update is available.

the problem is that also when I run the `guix package -u` to update the profile
my cron job still informs me about existence of new updates and the result of
`guix package -u -n` doesn't change. 

could anyone help me on this matter, or an alternate solution to check if any
update is available ( and get the list if it's possible )?

--
Regards
Reza Alizadeh Majd
PantherX Team