class GPGME::Ctx

def set_passphrase_callback(passfunc, hook_value = nil)

Other tags:
    Example: this will interactively ask for the password -
    Example: this method will simply return +maria+ as password. - 
def set_passphrase_callback(passfunc, hook_value = nil)
  GPGME::gpgme_set_passphrase_cb(self, passfunc, hook_value)
end