This program works with GnuPG 2 and later. GnuPG 1.x is not supported.
Passphrases set with this utility don't expire unless the --forget option is used to explicitly clear them from the cache --- or gpg-agent is either restarted or reloaded (by sending a SIGHUP to it). Note that the maximum cache time as set with --max-cache-ttl is still honored. It is necessary to allow this passphrase presetting by starting gpg-agent with the --allow-preset-passphrase.
gpg-preset-passphrase is invoked this way:
gpg-preset-passphrase [options] [command] cacheid
cacheid is either a 40 character keygrip of hexadecimal characters identifying the key for which the passphrase should be set or cleared. The keygrip is listed along with the key when running the command: gpgsm --with-keygrip --list-secret-keys. Alternatively an arbitrary string may be used to identify a passphrase; it is suggested that such a string is prefixed with the name of the application (e.g foo:12346). Scripts should always use the option --with-colons, which provides the keygrip in a "grp" line (cf. 'doc/DETAILS')/
One of the following command options must be given:
The following additional options may be used:
The full documentation for this tool is maintained as a Texinfo manual. If GnuPG and the info program are properly installed at your site, the command
should give you access to the complete manual including a menu structure and an index.