[systemd-devel] scope vs service units

[Lennart Poettering]

On Sun, 28.06.15 18:50, Michał Zegan (webczat_200 at poczta.onet.pl) wrote:

> Hey. I would like to ask about service vs scope units, both can be
> created programmatically, so what is a difference/usage scenario for
> programmatically created service vs scope units if service would have
> type simple?

Both service and scope units group processes. Service units however
cover processes that are forked off and started by PID 1 itself, while
scope units are something where external programs start the processes
and then just register them with PID 1 to wrap them in a scope unit.

Service units hence take as configuration parameters a command line to
execute and numerous execution-time settings, while in scope units the
essential configuration parameters are pretty much just a list of
PIDs, and no execution-time settings.

Both services and scopes can be created transiently via bus
calls. Howver only services may be created via unit files in
the file system.

Lennart

-- 
Lennart Poettering, Red Hat