allout-encrypt-string is a compiled Lisp function in `
(allout-encrypt-string TEXT DECRYPT ALLOUT-BUFFER KEYMODE-CUE &optional REJECTED)
Encrypt or decrypt message TEXT.
Returns the resulting string, or nil if the transformation fails.
If DECRYPT is true (default false), then decrypt instead of encrypt.
ALLOUT-BUFFER identifies the buffer containing the text.
Entry encryption defaults to symmetric key mode unless keypair
recipients are associated with the file (see
`epa-file-encrypt-to') or the function is invoked with a
(KEYMODE-CUE) universal argument greater than 1.
When encrypting, KEYMODE-CUE universal argument greater than 1
causes prompting for recipients for public-key keypair
encryption. Selecting no recipients results in symmetric key
Further, encrypting with a KEYMODE-CUE universal argument greater
than 4 - eg, preceded by a doubled Ctrl-U - causes association of
the specified recipients with the file, replacing those currently
associated with it. This can be used to dissociate any
recipients with the file, by selecting no recipients in the
Optional REJECTED is for internal use, to convey the number of
rejections due to matches against
`allout-encryption-ciphertext-rejection-regexps', as limited by
NOTE: A few GnuPG v2 versions improperly preserve incorrect
symmetric decryption keys, preventing entry of the correct key on
subsequent decryption attempts until the cache times-out. That
can take several minutes. (Decryption of other entries is not
affected.) Upgrade your EasyPG version, if you can, and you can
deliberately clear your gpg-agent's cache by sending it a '-HUP'