---
name: "sd_bus_reply_method_error"
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_reply_method_error"
---

# sd\_bus\_reply\_method\_error(3)

Reply with an error to a D-Bus method call

## NAME

sd\_bus\_reply\_method\_error, sd\_bus\_reply\_method\_errorf, sd\_bus\_reply\_method\_errorfv, sd\_bus\_reply\_method\_errno, sd\_bus\_reply\_method\_errnof, sd\_bus\_reply\_method\_errnofv - Reply with an error to a D-Bus method call

## SYNOPSIS

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

**int sd\_bus\_reply\_method\_error(sd\_bus\_message \****call***, const sd\_bus\_error \****e***);**

**int sd\_bus\_reply\_method\_errorf(sd\_bus\_message \****call***, const char \****name***, const char \****format***, ...);**

**int sd\_bus\_reply\_method\_errorfv(sd\_bus\_message \****call***, const char \****name***, const char \****format***, va\_list** *ap***);**

**int sd\_bus\_reply\_method\_errno(sd\_bus\_message \****call***, int** *error***, const sd\_bus\_error \****p***);**

**int sd\_bus\_reply\_method\_errnof(sd\_bus\_message \****call***, int** *error***, const char \****format***, ...);**

**int sd\_bus\_reply\_method\_errnofv(sd\_bus\_message \****call***, int** *error***, const char \****format***, va\_list** *ap***);**

## DESCRIPTION

The **sd\_bus\_reply\_method\_error()** function sends an error reply to the *call* message. The error structure *e* specifies the error to send, and is used as described in [**sd\_bus\_message\_new\_method\_error**(3)](/sd_bus_message_new_method_error/3.md). If no reply is expected to *call*, this function succeeds without sending a reply.

The **sd\_bus\_reply\_method\_errorf()** is to **sd\_bus\_reply\_method\_error()** what **sd\_bus\_message\_new\_method\_errorf()** is to **sd\_bus\_message\_new\_method\_error()**.

The **sd\_bus\_reply\_method\_errno()** is to **sd\_bus\_reply\_method\_error()** what **sd\_bus\_message\_new\_method\_errno()** is to **sd\_bus\_message\_new\_method\_error()**.

The **sd\_bus\_reply\_method\_errnof()** is to **sd\_bus\_reply\_method\_error()** what **sd\_bus\_message\_new\_method\_errnof()** is to **sd\_bus\_message\_new\_method\_error()**.

## RETURN VALUE

This function returns a non-negative integer if the error reply was successfully sent or if *call* does not expect a reply. On failure, it returns a negative errno-style error code.

### Errors

Returned errors may indicate the following problems:

**-EINVAL**

The input parameter *call* is **NULL**.

Message *call* is not a method call message.

Message *call* is not attached to a bus.

The error parameter *e* to **sd\_bus\_reply\_method\_error()** is not set, see [**sd\_bus\_error\_is\_set**(3)](/sd_bus_error_is_set/3.md).

**-EPERM**

Message *call* has been sealed.

**-ENOTCONN**

The bus to which message *call* is attached is not connected.

**-ENOMEM**

Memory allocation failed.

In addition, any error returned by [**sd\_bus\_send**(3)](/sd_bus_send/3.md) may be returned.

## 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.

## SEE ALSO

[**systemd**(1)](/systemd/1.md), [**sd-bus**(3)](/sd-bus/3.md), [**sd\_bus\_message\_new\_method\_error**(3)](/sd_bus_message_new_method_error/3.md)