Explicitly check status code after Exec
Explicitly check status code after Exec

If the exec fails (e.g. because the container is not running), we should print
the resulting error message instead of always trying to get the process' exit
code (which wouldn't exist if the container wasn't running, because the
process never actually got exec'd).

Signed-off-by: Tycho Andersen <10c18fcb898ee6b17d6575d444b125d10b3f4d6a@canonical.com>

jensg-st/lxd,rrva/lxd,sl1pm4t/lxd,erikmack/lxd,hallyn/lxd,jsavikko/lxd,mjeanson/lxd,sl1pm4t/lxd,tych0/lxd,georghopp/lxd,techtonik/lxd,ollie314/lxd,mjeanson/lxd,chrisglass/lxd,rcj4747/lxd,ericsnowcurrently/lxd,rcj4747/lxd,dustinkirkland/lxd,techtonik/lxd,rrva/lxd,dustinkirkland/lxd,chrisglass/lxd,smoser/lxd,mikemccracken/lxd,atxwebs/lxd,smoser/lxd,atxwebs/lxd,dvbportal/osx-lxd,akshaykarle/lxd,pcdummy/lxd,basvanbeek/lxd,lxc/lxd,lxc/lxd,stgraber/lxd,lxc/lxd,achanda/lxd,tych0/lxd,pcdummy/lxd,stgraber/lxd,basvanbeek/lxd,ollie314/lxd,Malizor/lxd,atxwebs/lxd,benaryorg/lxd,beni55/lxd,dustinkirkland/lxd,benaryorg/lxd,benaryorg/lxd,jsavikko/lxd,mikemccracken/lxd,ericsnowcurrently/lxd,erikmack/lxd,stgraber/lxd,basvanbeek/lxd,yura-pakhuchiy/lxd,ollie314/lxd,jensg-st/lxd,lxc/lxd,pcdummy/lxd,hallyn/lxd,beni55/lxd,Skarlso/lxd,stgraber/lxd,stgraber/lxd,beni55/lxd,achanda/lxd,erikmack/lxd,stgraber/lxd,sl1pm4t/lxd,Malizor/lxd,jumpstarter-io/lxd,dvbportal/osx-lxd,rcj4747/lxd,Malizor/lxd,rrva/lxd,georghopp/lxd,hallyn/lxd,tych0/lxd,mjeanson/lxd,atxwebs/lxd,chrisglass/lxd,hallyn/lxd,lxc/lxd,Skarlso/lxd,stgraber/lxd,hallyn/lxd,yura-pakhuchiy/lxd,jsavikko/lxd,akshaykarle/lxd,lxc/lxd,Skarlso/lxd,techtonik/lxd,lxc/lxd,ericsnowcurrently/lxd,yura-pakhuchiy/lxd,dvbportal/osx-lxd,achanda/lxd,smoser/lxd,jensg-st/lxd,Skarlso/lxd,jumpstarter-io/lxd,akshaykarle/lxd,mikemccracken/lxd,georghopp/lxd,hallyn/lxd,jumpstarter-io/lxd