PAM_TRY_AGAIN
if (error == PAM_TRY_AGAIN) {
if (pam_retval == PAM_TRY_AGAIN) {
case PAM_TRY_AGAIN:
err == PAM_TRY_AGAIN) &&
error == PAM_TRY_AGAIN) &&
err == PAM_TRY_AGAIN) &&
case PAM_TRY_AGAIN:
if (retval == PAM_TRY_AGAIN)
case PAM_TRY_AGAIN: