Check if a reboot is required after installing Linux updates

RedHat OS family

[user1@alma9 ~]$ sudo dnf install yum-utils

[user1@alma9 ~]$ sudo needs-restarting  -r ; echo $?
[sudo] password for deploy: 
No core libraries or services have been updated since boot-up.
Reboot should not be necessary.
0

[user1@alma9 ~]$ sudo needs-restarting -s

Debian OS family

user1@ip-172-26-3-50:~$ cat /var/run/reboot-required
*** System restart required ***
user1@ip-172-26-3-50:~$ cat /var/run/reboot-required.pkgs
libssl1.1
dbus
dbus
linux-image-5.13.0-1023-aws
linux-base
linux-image-5.13.0-1025-aws
linux-base
linux-image-5.13.0-1028-aws
linux-base
linux-image-5.13.0-1029-aws
linux-base
linux-image-5.13.0-1031-aws
linux-base
libssl1.1
libssl1.1