Re: autodetecting init system.

[John Spray <john.spray@redhat.com>]

On 11/05/2015 17:29, Owen Synge wrote:
> Dear all,
>
> Many init systems are used in linux now. Some ceph code needs to know
> the init system. (I must admit I have not looked into Solaris, MacOS and
> BSD and probably should have)
>
> It would be nice to have one function that detects the init system
>
> Since the init system can be specified in ceph and ceph-deploy
> explicitly it seems to be its reasonable to fail clearly to detect init
> system.
I think I'm missing some background here.  I was under the impression 
that distros generally had a preferred init system (even if they let you 
switch), and if another is in use then compatibility links are usually 
provided (e.g. sysv-style calling through to systemd or vice versa).  
Given that, the distro packaging then uses whatever the "right" way to 
start a service is for that distro, and it's up to the distro to make 
sure that command is available.

Otherwise don't we descend into a kind of madness where a package 
post-install script can't start a service, because it doesn't know what 
command to run?

Cheers,
John