Send a service stop, start, restart or status instruction to Upstart (via initctl) or systemd (via systemctl) as appropriate. Relevant on e.g. Ubuntu Xenial, which uses systemd for its init, but still retains Upstart for certain Unity-related purposes.

daemonctl

#!/usr/bin/env python

import subprocess, os, sys

DEVNULL = open(os.devnull,"r+")

ctlexes = ["initctl","systemctl"]

provides = ["start","stop","restart","status"]

sys.argv[0] = os.path.basename(sys.argv[0])
if sys.argv[0] not in provides:
    sys.argv.pop(0)

if (not sys.argv) or (sys.argv[0] not in provides): #ie still
    raise RuntimeError("must be used for commands of %r only (not %s)"%(provides,sys.argv[0]))

for a in sys.argv[1:]:
    if a[0] != "-":
        dae = a
        break
else:
    raise RuntimeError("no daemon specified")

for myctl in ctlexes:
    ret = subprocess.call([myctl,"status",dae],stdout=DEVNULL,stderr=DEVNULL,stdin=DEVNULL)
    if not ret:
        ctl = myctl
        break
else:
    raise RuntimeError("daemon name %s not recognised by any of %r"%(dae,ctlexes))

sys.exit(subprocess.call([myctl]+sys.argv))