+### this return True or False to indicate that systemctl is present on that box
+# cache result in memory as _has_systemctl
+_has_systemctl=None
+def has_systemctl ():
+ global _has_systemctl
+ if _has_systemctl is None:
+ _has_systemctl = (subprocess.call([ 'systemctl', '--help' ]) == 0)
+ return _has_systemctl
+
+# how to run a command in a slice
+# now this is a painful matter
+# the problem is with capsh that forces a bash command to be injected in its exec'ed command
+# so because lxcsu uses capsh, you cannot exec anything else than bash
+# bottom line is, what actually needs to be called is
+# vs: vserver exec slicename command and its arguments
+# lxc: lxcsu slicename "command and its arguments"
+# which, OK, is no big deal as long as the command is simple enough,
+# but do not stretch it with arguments that have spaces or need quoting as that will become a nightmare