---
name: "sasl_checkapop"
section: "3"
platform: "linux"
package: "libsasl2-dev"
version: "2.1.28+dfsg1-9"
release: "Debian 13 (Trixie)"
platforms: ["linux", "macos"]
url: "https://new.carta.tech/sasl_checkapop"
---

# sasl\_checkapop(3)

Cyrus SASL documentation

## NAME

sasl\_checkapop - Cyrus SASL documentation

## SYNOPSIS

```
#include <sasl/sasl.h>
int sasl_checkapop(sasl_conn_t *conn,
                 const char *challenge,
                 unsigned challen,
                 const char *response,
                 unsigned resplen)
```

## DESCRIPTION

- **int sasl\_checkapop(sasl\_conn\_t \*conn,**

  - **const char \*challenge,**

  - **unsigned challen,**

  - **const char \*response,**

  - **unsigned resplen)**

  **sasl\_checkapop**  will  check  an APOP challenge/response. APOP is an optional POP3 (*RFC 1939*) authentication command which  uses  a  shared  secret (password). The password is stored in the SASL secrets database.  For  information  on the  SASL  shared secrets database see the *System Administrators Guide*.

  If  called  with  a  NULL challenge, sasl\_checkapop() will check to see if the APOP mechanism is enabled.

## RETURN VALUE

sasl\_checkapop returns an integer which corresponds to one of the following codes. *SASL\_OK* indicates that the authentication is complete.  All  other  return  codes  indicate errors  and should either be handled or the authentication session should be quit.  See *[sasl\_errors(3)](/sasl_errors/3.md)*  for  meanings of return codes.

## CONFORMING TO

*RFC 4422*, *RFC 1939*

## SEE ALSO

*[sasl(3)](/sasl/3.md)*, *[sasl\_errors(3)](/sasl_errors/3.md)*

## AUTHOR

The Cyrus Team

## COPYRIGHT

1993-2016, The Cyrus Team