[julia-users] wait/notify from a thread?

[Tim Holy]

I'm interfacing with a C library that provides the ability to set a callback 
function so you can be notified when some job is done. I'm hoping to exploit 
this with the Task interface so I can feed multiple jobs with a single Julia 
process. I'm declaring my notify function like this:

function callback_notify(hnd, status, data)
    println("In notify")
    s = unsafe_pointer_to_objref(data)::Stream
    @show s
    s.status = status
    notify(s.c)
    println("Done notifying")
    nothing
end

Stream is a type that has a Condition member,
type Stream
    handle::StreamHandle
    status::Cuint
    c::Condition
end

I've successfully set the callback function, issued wait(s.c), and from the 
println statements I can see that the notify callback executes fully. However, 
my task never wakes up. My suspicion is that the C library is spawning a new 
thread; does that pose problems for the Task interface? Or is something else 
happening? Any good workarounds?

--Tim