[HEADS-UP] systemd for F14 - the next steps

Lennart Poettering mzerqung at 0pointer.de
Fri Jul 23 00:54:49 UTC 2010


On Thu, 22.07.10 19:06, Chris Adams (cmadams at hiwaay.net) wrote:

> 
> Once upon a time, Lennart Poettering <mzerqung at 0pointer.de> said:
> > Same with systemd. If you use "systemctl status foo.service" the output
> > is human readable. If it is "systemctl show foo.service" it is computer
> > parsable. Just a slightly different command of the systemctl tool.
> 
> Again: this is confusing!  There should be one (and only one) command to
> show information.  It should accept arguments to modify that output,
> e.g. default to brief info, -v gets a little more info, -vv gets all
> kinds of info, -p to get "parseable" output (or -f for "formatted"),
> etc.

"show" actually gives you full access to all properties of a
service. It's a long list. It gives you runtime parameters as well as
the stuff you configured in your unit file or which was implied form the
defaults. It is also sometimes a little bit too much for people to
grasp, since for example it shows the full set of dependencies that are
implicitly added to most services. We certainly don't want to show this
to our users most of the time. 

So, "show" is very verbose. On the other hand "status" is pretty
short. It only shows runtime information and that in a hightly reduced
way. For example fields are suppressed depending on the state of the
unit and other fields are shown, and then shows the process tree for
this. It also ellipsizes and aligns the output, and applies coloring (in
case the unit is in some 'maintenance' state, i.e. crashed, exited with
non-zero exit code, timed out, yadda yadda).

I think the differences between the two commands are sufficiently big to
warrant the two seperate commands.

> Having "status" and "show" give the same info in different formats will
> always be confusing.  People won't remember which is which (because the
> works mean similar things in this context) and will run the wrong one
> for what they want about 50% of the time (which will just be
> frustrating).

You are discussing something you never actually played around
with... 

Trust me, the output of the two commands is sufficiently different to
not confuse anybody.

Lennart

-- 
Lennart Poettering - Red Hat, Inc.


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