Cross-Platform equivalent to windows events

Fire_Lancer_6266 0
Viewed 18628

I'm trying to port some Windows code to Linux, ideally through platform-independent libraries (eg boost), however I'm not sure how to port this bit of event code.

The bit of code involves two threads (lets call them A and B). A wants to do something that only B can, so it sends B a message, then waits for B to say its done. In windows this looks something like:

void foo();//thread a calls this
void bar(HANDLE evt);

void foo()
{
    HANDLE evt = CreateEvent(0,FALSE,FALSE,0);
    bCall(boost::bind(&bar, evt));
    WaitForSingleObject(evt,INFINITE);
    CloseHandle(evt);
}
void bar(HANDLE evt)
{
    doSomething();
    SetEvent(evt);
}

I looked at the boost::thread library, but it didnt seem to have anything that does this, the closes I could see was the boost::condition_variable, but it appears that is means in conjunction with a mutex, which is not the case here.

multithreading cross-platform boost windows c++
10 Answers

You could use a promise and a future, from boost thread:

#include <boost\thread.hpp>

boost::promise<bool> prom;

void foo()
{
    auto future = prom.get_future();
    auto result = future.wait_for(boost::chrono::milliseconds(1000));
    // we get here if (a) 1 second passes or (b) bar sets the promise value
    if (result==boost::future_status::ready) 
    { 
        /* bar set the promise value */ 
    }
    if (result==boost::future_status::timeout)
    {
        /* 1 second passed without bar setting promise value */ 
    }
}

void bar()
{
    prom.set_value(true);
}
user_30426910
Related