A stray keeps turning up extremely hungry, with a strong urge to stay.
He's very affectionate, and rather clean and seemingly healthy, so we're
all okay with him staying.  However, we don't want him in when everyone's
out (since then we can't turn the alarm on) or when everyone's asleep (what
if he wants to go out?), so we leave him outside at these times.

Specifically, we sleep between 11pm and 7am, so he's out all night.  We
then feed him at 7am and put him out again until someone comes home, at
4pm.  Then from 4pm to 11pm he can stay.

Is being outside for this long okay for a cat?  Since some articles on
<http://cats.about.com/> suggest that people should actually aim to keep
cats *indoors*, I'm a little uncertain.

Should we carry on as we are, or should we try and find another owner who
can keep it in for as long as it wants?

Also, this cat seems to want to sleep a lot when it's indoors, suggesting
that it doesn't get much/any sleep outside.  Do cats generally sleep
outside?

Thanks for any advice!