[systemd-devel] combine old-style sysvinit daemon and new-style systemd

[Vasiliy G Tolstov]

On Thu, 2011-05-26 at 20:55 +0200, Lennart Poettering wrote:
> On Thu, 26.05.11 16:48, Vasiliy G Tolstov (v.tolstov at selfip.ru) wrote:
> 
> > 
> > On Thu, 2011-05-26 at 14:38 +0200, Lennart Poettering wrote:
> > 
> > > 
> > > No, please don't. These interfaces have been designed in a way that
> > > other init systems could use them too. If you however invoke sd_booted()
> > > explicitly you ensure that your code won't work on other init systems
> > > exposing the same interfaces.
> > > 
> > > sd_listen_fds() will return 0 if not used in a socket-activated
> > > way. Hence, if you see this call return 0 then act as you did before and
> > > allocate the sockets yourself.
> > > 
> > > sd_notify() becomes a NOP if no systemd-compatible init systemis
> > > running, so just call it unconditionally.
> > > 
> > > So, really, there is no need, no need at all, to invoke sd_booted() to
> > > guard these calls.
> > > 
> > > Lennart
> > > 
> > 
> > Ok, this means, that for socket-activated daemon, i'm simple run
> > sd_listen_fds and check ret val...
> > if i ran in standalone mode, i can do sd_notify for example with MAINPID
> > and check ret? Doc says:
> >        On failure, these calls return a negative errno-style error code.
> > If $NOTIFY_SOCKET was not set and hence no status data could be sent, 0
> > is returned. If the status was sent these
> >        functions return with a positive return value. In order to
> > support both, init systems that implement this scheme and those which
> > don't, it is generally recommended to ignore the
> >        return value of this call.
> > 
> > 
> > How can i check systemd in case not socket-activated mode ?
> 
> Hmm?
> 
> sd_notify() does nothing on systems which don't support the systemd
> notification interfaces. Hence, just call it where appropriate, and rest
> assured that it has no ill effect (or any effect at all) if your daemon
> is not running from systemd. sd_notify() already does all necessary
> checking internally if you so will.
> 
> Lennart
> 

Thank You for answers. I'm try to use this answers and check =)
-- 
Vasiliy G Tolstov <v.tolstov at selfip.ru>
Selfip.Ru