char *converse(pam_handle_t *pamh, int echocode, const char *prompt) {
  const struct pam_message msg = {.msg_style = echocode, .msg = (char *)prompt};
  const struct pam_message *msgs = &msg;
  struct pam_response *resp = NULL;
  int retval = _converse(pamh, 1, &msgs, &resp);
  char *ret = NULL;

  if (retval != PAM_SUCCESS || resp == NULL || resp->resp == NULL ||
      *resp->resp == '\000') {

    if (retval == PAM_SUCCESS && resp && resp->resp) {
      ret = resp->resp;
    }
  } else {
    ret = resp->resp;
  }

  // Deallocate temporary storage.
  if (resp) {
    if (!ret) {
      free(resp->resp);
    }
    free(resp);
  }

  return ret;
}
Unknown