Как шифровать и подписывать ключем gpg?

--default-cache-ttl n  -  Set  the  time  a cache entry is valid to n seconds.  The default is 600 seconds.  Each time a cache entry is accessed, the entry's timer is reset.  To set an entry's  maximum lifetime, use ax-cache-ttl.  Note that a cached passphrase may not evicted immediately from memory if no client requests a cache operation.  This is due to an internal housekeeping function which is only run every few seconds.
--max-cache-ttl n  -  Set  the maximum time a cache entry is valid to n seconds.  After this time a cache entry will be expired even if it has been accessed recently or has been  set  using  gpg-preset-passphrase.  The default is 2 hours (7200 seconds).

default-cache-ttl 0
max-cache-ttl 0