---
name: "sd_bus_list_names"
section: "3"
platform: "linux"
package: "systemd-libs"
version: "262.1-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/sd_bus_list_names"
---

# sd\_bus\_list\_names(3)

Retrieve information about registered names on a bus

## NAME

sd\_bus\_list\_names - Retrieve information about registered names on a bus

## SYNOPSIS

```
#include <systemd/sd-bus.h>
```

**int sd\_bus\_list\_names(sd\_bus \****bus***, char \*\*\****acquired***, char \*\*\****activatable***);**

## DESCRIPTION

**sd\_bus\_list\_names()** retrieves information about the registered names on a bus. If *acquired* is not **NULL**, this function calls **org.freedesktop.DBus.ListNames**\[1\] to retrieve the list of currently-owned names on the bus. If *activatable* is not **NULL**, the function calls **org.freedesktop.DBus.ListActivatableNames**\[2\] to retrieve the list of all names on the bus that can be activated. Note that ownership of the arrays returned by **sd\_bus\_list\_names()** in *acquired* and *activatable* is transferred to the caller and hence, the caller is responsible for freeing these arrays and their contents.

## RETURN VALUE

On success, **sd\_bus\_list\_names()** returns a non-negative integer. On failure, it returns a negative errno-style error code.

### Errors

Returned errors may indicate the following problems:

**-EINVAL**

*bus* or both *acquired* and *activatable* were **NULL**.

**-ENOPKG**

The bus cannot be resolved.

**-ECHILD**

The bus was created in a different process, library or module instance.

**-ENOMEM**

Memory allocation failed.

**-ENOTCONN**

The bus is not connected.

## NOTES

Functions described here are available as a shared library, which can be compiled against and linked to with the **libsystemd** [**pkg-config**(1)](/pkg-config/1.md) file.

All functions listed here are thread-agnostic and only a single thread may operate on a given object at any given time. Different threads may access the same object at different times. Multiple independent objects may be used from different threads in parallel.

The code described here uses [**getenv**(3)](/getenv/3.md), which is declared to be not multi-thread-safe. This means that the code calling the functions described here must not call [**setenv**(3)](/setenv/3.md) from a parallel thread. It is recommended to only do calls to **setenv()** from an early phase of the program when no other threads have been started.

## HISTORY

**sd\_bus\_list\_names()** was added in version 221.

## SEE ALSO

[**systemd**(1)](/systemd/1.md), [**sd-bus**(3)](/sd-bus/3.md)

## NOTES

- 1\.

  org.freedesktop.DBus.ListNames

  https://dbus.freedesktop.org/doc/dbus-specification.html#bus-messages-list-names

- 2\.

  org.freedesktop.DBus.ListActivatableNames

  https://dbus.freedesktop.org/doc/dbus-specification.html#bus-messages-list-activatable-names