---
name: "setauid"
section: "2"
platform: "macos"
package: "xnu"
version: "12377.121.6"
release: "macOS 26.5"
platforms: ["freebsd", "macos"]
url: "https://new.carta.tech/setauid"
---

# setauid(2)

set audit indentifier

## NAME

**setauid** – set audit indentifier

## SYNOPSIS

**#include \<bsm/audit.h\>**

*int*\

**setauid**(*au\_id\_t \*auid*);

## DESCRIPTION

The **setauid**() system call sets the active audit identifier for the current process from the *au\_id\_t* pointed to by *auid*. The value of AU\_DEFAUDITID (-1) should not be used for  *auid*.

This system call requires an appropriate privilege to complete.

Once the audit identifier is set to some other value than AU\_DEAUDITID (-1) then it is immutable. This system call may be used to set the audit identifier after  initially setting up the audit session with the  [setaudit(2)](/setaudit/2.md), or  [setaudit\_addr(2)](/setaudit_addr/2.md) system call.

## RETURN VALUES

The **setauid()** function returns the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to indicate the error.

## ERRORS

The **setauid**() function will fail if:

- \[EFAULT\]

  A failure occurred while data transferred to the kernel failed.

- \[EINVAL\]

  An invalid value for  *auid* was used. *auid* can be any value of type  *au\_id\_t* except AU\_DEFAUDITID.

- \[EPERM\]

  The process does not have sufficient permission to complete the operation.

## SEE ALSO

[audit(2)](/audit/2.md), [auditon(2)](/auditon/2.md), [getaudit(2)](/getaudit/2.md), [getaudit\_addr(2)](/getaudit_addr/2.md), [getauid(2)](/getauid/2.md), [setaudit(2)](/setaudit/2.md), [setaudit\_addr(2)](/setaudit_addr/2.md), [libbsm(3)](/libbsm/3.md)

## HISTORY

The OpenBSM implementation was created by McAfee Research, the security division of McAfee Inc., under contract to Apple Computer Inc. in 2004. It was subsequently adopted by the TrustedBSD Project as the foundation for the OpenBSM distribution.

## AUTHORS

This software was created by McAfee Research, the security research division of McAfee, Inc., under contract to Apple Computer Inc. Additional authors include Wayne Salamon, Robert Watson, and SPARTA Inc.

The Basic Security Module (BSM) interface to audit records and audit event stream format were defined by Sun Microsystems.

This manual page was written by Robert Watson ⟨rwatson@FreeBSD.org⟩ and Stacey Son ⟨sson@FreeBSD.org⟩.