---
name: "openpam_nullconv"
section: "3"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["freebsd", "macos"]
url: "https://new.carta.tech/openpam_nullconv"
---

# openpam\_nullconv(3)

null conversation function

## NAME

**openpam\_nullconv** – null conversation function

## SYNOPSIS

**#include \<sys/types.h\>**

**#include \<security/pam\_appl.h\>**

**#include \<security/openpam.h\>**

*int*\

**openpam\_nullconv**(*int n*, *const struct pam\_message \*\*msg*, *struct pam\_response \*\*resp*, *void \*data*);

## DESCRIPTION

The **openpam\_nullconv**() function is a null conversation function suitable for applications that want to use PAM but don't support interactive dialog with the user. Such applications should set PAM\_AUTHTOK to whatever authentication token they've obtained on their own before calling [pam\_authenticate(3)](/pam_authenticate/3.md) and / or [pam\_chauthtok(3)](/pam_chauthtok/3.md), and their PAM configuration should specify the use\_first\_pass option for all modules that require access to the authentication token, to make sure they use PAM\_AUTHTOK rather than try to query the user.

## RETURN VALUES

The **openpam\_nullconv**() function returns one of the following values:

- \[PAM\_SUCCESS\]

  Success.

- \[PAM\_CONV\_ERR\]

  Conversation failure.

## SEE ALSO

[openpam\_ttyconv(3)](/openpam_ttyconv/3.md), [pam(3)](/pam/3.md), [pam\_authenticate(3)](/pam_authenticate/3.md), [pam\_chauthtok(3)](/pam_chauthtok/3.md), [pam\_prompt(3)](/pam_prompt/3.md), [pam\_set\_item(3)](/pam_set_item/3.md), [pam\_strerror(3)](/pam_strerror/3.md), [pam\_vprompt(3)](/pam_vprompt/3.md)

## STANDARDS

The **openpam\_nullconv**() function is an OpenPAM extension.

## AUTHORS

The **openpam\_nullconv**() function and this manual page were developed for the FreeBSD Project by ThinkSec AS and Network Associates Laboratories, the Security Research Division of Network Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 (“CBOSS”), as part of the DARPA CHATS research program.

The OpenPAM library is maintained by Dag-Erling Smørgrav ⟨*des@des.dev*⟩.