---
name: "utmpx"
section: "5"
platform: "macos"
package: "Libc"
version: "1752.120.2"
release: "macOS 26.5"
platforms: ["linux", "macos"]
url: "https://new.carta.tech/utmpx/5"
---

# utmpx(5)

user accounting database

## NAME

**utmpx** – user accounting database

## SYNOPSIS

**#include \<utmpx.h\>**

## DESCRIPTION

In contrast to *utmp* and *wtmp*, the extended databases in *utmpx* and *wtmpx* reserve more space for logging hostnames, and also information on a process' ID, termination signal and exit status.

The ⟨*utmpx.h*⟩ header defines the structures and functions for logging user. Currently logged in users are tracked in */var/run/utmpx*. The interface to the **utmpx** file is described in [endutxent(3)](/endutxent/3.md). The file is not automatically created if they do not exist; it must be created manually.

Traditionally, separate files would be used to store the running log of the logins and logouts (*wtmpx*), and the last login of each user (*lastlogx*). With the availability of the Apple system log facility [asl(3)](/asl/3.md), these separate files can be replace with log entries, which are automatically generated when **utmpx** entries are written. The API to access the logins and logouts is described in endutxent\_wtmp(3) while the last login info is accessible with [getlastlogx(3)](/getlastlogx/3.md).

For compatibility, changes to **utmpx** are reflected in utmp(3) (in the *utmp*, *wtmp* and *lastlog* files), but not the other way around.

## FILES

- */var/run/utmpx*

  The **utmpx** file.

## SEE ALSO

[asl(3)](/asl/3.md), [endutxent(3)](/endutxent/3.md), endutxent\_wtmp(3), [getlastlogx(3)](/getlastlogx/3.md), [utmp(5)](/utmp/5.md)