What is the function of the apt-key command in Linux?

The “apt-key” command in Linux is used to manage the keys used by the APT package management system. It can be used to add, remove, list, and update keys.

Specifically, the function of the apt-key command is as follows:

1. Add the key: You can import the public key of third-party software sources using the apt-key command. This way, APT can verify the authenticity of the software packages.
2. Delete keys: You can remove unwanted keys using the apt-key command.
3. List the keys: Use the apt-key command to list all keys imported on the current system.
4. Update keys: You can use the apt-key command to refresh imported keys to keep them valid.

In short, the apt-key command is used to manage the keys used by the APT software package management system, enhancing system security and the credibility of software packages.