---
name: "CURLOPT_SASL_AUTHZID"
section: "3"
platform: "linux"
package: "curl"
version: "8.23.0-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux", "macos"]
url: "https://new.carta.tech/CURLOPT_SASL_AUTHZID"
---

# CURLOPT\_SASL\_AUTHZID(3)

authorization identity (identity to act as)

## NAME

CURLOPT\_SASL\_AUTHZID - authorization identity (identity to act as)

## SYNOPSIS

```
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SASL_AUTHZID, char *authzid);
```

## DESCRIPTION

Pass a char pointer as parameter, which should be pointing to the null-terminated authorization identity (*authzid*) for the transfer. Only applicable to the PLAIN SASL authentication mechanism where it is optional.

When not specified only the authentication identity (*authcid*) as specified by the username is sent to the server, along with the password. The server derives a *authzid* from the *authcid* when not provided, which it then uses internally.

When the *authzid* is specified, the use of which is server dependent, it can be used to access another user's inbox, that the user has been granted access to, or a shared mailbox for example.

The application does not have to keep the string around after setting this option.

Using this option multiple times makes the last set string override the previous ones. Set it to NULL to disable its use again.

## DEFAULT

blank

## PROTOCOLS

This functionality affects imap only

## EXAMPLE

```
int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode result;
    curl_easy_setopt(curl, CURLOPT_URL, "imap://example.com/");
    curl_easy_setopt(curl, CURLOPT_USERNAME, "Kurt");
    curl_easy_setopt(curl, CURLOPT_PASSWORD, "xipj3plmq");
    curl_easy_setopt(curl, CURLOPT_SASL_AUTHZID, "Ursel");
    result = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}
```

## AVAILABILITY

Added in curl 7.66.0

## RETURN VALUE

*[curl\_easy\_setopt(3)](/curl_easy_setopt/3.md)* returns a CURLcode indicating success or error.

CURLE\_OK (0) means everything was OK, non-zero means an error occurred, see *[libcurl-errors(3)](/libcurl-errors/3.md)*.

## SEE ALSO

[**CURLOPT\_PASSWORD**(3)](/CURLOPT_PASSWORD/3.md), [**CURLOPT\_USERNAME**(3)](/CURLOPT_USERNAME/3.md), [**CURLOPT\_USERPWD**(3)](/CURLOPT_USERPWD/3.md)