…been searching for the equivalent command to yum check-update for Ubuntu and Debian, and thanks to some Google searching, found what I needed, as follows:
1. sudo apt-get update
…to ensure you have the latest package index files, then
2. sudo aptitude search ‘~U’
You can use the equivalent:
sudo aptitude search ‘?upgradable’
…but I thought folks could trip over the spelling of upgradable -vs- upgradeable (the latter won’t work)
Hope this helps!