Is it possible to export a GPG private key without passphrase being provided in a prompt?

I would like to automate a GPG private key export so it runs without user interaction.

gpg --export-secret-keys [e-mail]

I tried providing --batch --passphrase-fd 0 arguments both with passphrase being passsed as:

• an argument --passphrase 'my-passhrase'
• from stdin echo 'my-passphrase' | gpg ...

It didn’t work. Is it even possible to export private keys without user interaction?

Answer

You should add --pinentry-mode=loopback parameter, as well as --batch. Full example from the RNP CLI tests suite:

gpg --batch --homedir .gpg ----pinentry-mode=loopback --yes --passphrase "password" --output keyfile.asc --export-secret-key userid