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# go-systemd
[](https://pkg.go.dev/mod/github.com/coreos/go-systemd/v22/?tab=packages)
Go bindings to systemd. The project has several packages:
- `activation` - for writing and using socket activation from Go
- `daemon` - for notifying systemd of service status changes
- `dbus` - for starting/stopping/inspecting running services and units
- `journal` - for writing to systemd's logging service, journald
- `sdjournal` - for reading from journald by wrapping its C API
- `login1` - for integration with the systemd logind API
- `machine1` - for registering machines/containers with systemd
- `unit` - for (de)serialization and comparison of unit files
## Socket Activation
An example HTTP server using socket activation can be quickly set up by following this README on a Linux machine running systemd:
https://github.com/coreos/go-systemd/tree/main/examples/activation/httpserver
## systemd Service Notification
The `daemon` package is an implementation of the [sd_notify protocol](https://www.freedesktop.org/software/systemd/man/sd_notify.html#Description).
It can be used to inform systemd of service start-up completion, watchdog events, and other status changes.
## D-Bus
The `dbus` package connects to the [systemd D-Bus API](http://www.freedesktop.org/wiki/Software/systemd/dbus/) and lets you start, stop and introspect systemd units.
[API documentation][dbus-doc] is available online.
[dbus-doc]: https://pkg.go.dev/github.com/coreos/go-systemd/v22/dbus?tab=doc
### Debugging
Create `/etc/dbus-1/system-local.conf` that looks like this:
```
<!DOCTYPE busconfig PUBLIC
"-//freedesktop//DTD D-Bus Bus Configuration 1.0//EN"
"http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd">
<busconfig>
<policy user="root">
<allow eavesdrop="true"/>
<allow eavesdrop="true" send_destination="*"/>
</policy>
</busconfig>
```
## Journal
### Writing to the Journal
Using the pure-Go `journal` package you can submit journal entries directly to systemd's journal, taking advantage of features like indexed key/value pairs for each log entry.
### Reading from the Journal
The `sdjournal` package provides read access to the journal by wrapping around journald's native C API; consequently it requires cgo and the journal headers to be available.
## logind
The `login1` package provides functions to integrate with the [systemd logind API](http://www.freedesktop.org/wiki/Software/systemd/logind/).
## machined
The `machine1` package allows interaction with the [systemd machined D-Bus API](http://www.freedesktop.org/wiki/Software/systemd/machined/).
## Units
The `unit` package provides various functions for working with [systemd unit files](http://www.freedesktop.org/software/systemd/man/systemd.unit.html).
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