[CentOS] how to find out the number of updates for a system

Wed May 22 13:44:28 UTC 2019
mark <m.roth at 5-cent.us>

Ralf Prengel wrote:
> Hallo,
> I need the information how many updates are available for a system.
> What is the best way to find it out in a one line bash script.
yum check-update, perhaps?