Note that if usage of apt-key is desired the additional installation of the GNU Privacy Guard suite (packaged in gnupg) is required. For this reason alone the programmatic usage (especially in package maintainer scripts!) is strongly discouraged. Further more the output format of all commands is undefined and can and does change whenever the underlying commands change. apt-key will try to detect such usage and generates warnings on stderr in these cases.
apt-key supports only the binary OpenPGP format (also known as "GPG key public ring") in files with the "gpg" extension, not the keybox database format introduced in newer gpg(1) versions as default for keyring files. Binary keyring files intended to be used with any apt version should therefore always be created with gpg --export.
Alternatively, if all systems which should be using the created keyring have at least apt version >= 1.4 installed, you can use the ASCII armored format with the "asc" extension instead which can be created with gpg --armor --export.
It is critical that keys added manually via apt-key are verified to belong to the owner of the repositories they claim to be for otherwise the apt-secure(8) infrastructure is completely undermined.
Note: Instead of using this command a keyring should be placed directly in the /etc/apt/trusted.gpg.d/ directory with a descriptive name and either "gpg" or "asc" as file extension.
Note that a distribution does not need to and in fact should not use this command any longer and instead ship keyring files in the /etc/apt/trusted.gpg.d/ directory directly as this avoids a dependency on gnupg and it is easier to manage keys by simply adding and removing files for maintainers and users alike.
Note that options need to be defined before the commands described in the previous section.
m[blue]APT bug pagem. If you wish to report a bug in APT, please see /usr/share/doc/debian/bug-reporting.txt or the reportbug(1) command.
APT was written by the APT team <firstname.lastname@example.org>.