Removing gpg keys

gpg keys can normally be removed from the /etc/apt/trusted.gpg.d directory.

This would be in the format of sudo rm ...

However if the keys are stored in /etc/apt/trusted.gpg then we need to use;

sudo apt-key del [keyid] which is fine for older? systems where the following shows a list of the keys;

sudo apt-key list

and the keyid field would be shown but on modern systems that seems not to be the case, so this time, we again use sudo apt-key list but note the last 8 characters of the long number and this becomes the keyid which can then be removed by using;

sudo apt-key del [keyid]

gzip -l shows incorrect uncompressed file size

In some cases the incorrect uncompressed file size is reported when running the following command;

gzip -l myfile.gz

A work around is the use the alternative below;

zcat myfile.ga | wc -c

[source]

Resize a VistualBox disk

To resize a virtualbox disk, you can do it from the GUI on current systems;