How to load an ASIO driver in C++?

Question

I want to access the list of driver's names with the C++ ASIO SDK of Steinberg to select the driver then load it. So I try to use the hostsample.cpp exemple to write my code, it compile but dont want to execute:

#include <iostream>
#include <thread>

#include "asio.h"
#include "asiodrivers.h"

//----DBG MACROS----//
#define DBG(x) std::cout << #x << ": " << x << std::endl;
#define NL std::cout << std::endl; //new line
//------------------//

extern AsioDrivers *asioDrivers;
bool loadAsioDriver(char *name);

void audioTask(void)
{
    auto maxDrivers {asioDrivers->asioGetNumDev()}; //The problem is here

    ASIODriverInfo drvInfo{};
    ASIOInit(&drvInfo);

    //print info
    NL;
    DBG(drvInfo.asioVersion);
    DBG(drvInfo.driverVersion);
    DBG(drvInfo.errorMessage);
    DBG(drvInfo.name);
    DBG(drvInfo.sysRef);
}

int main(void)
{
    std::thread audioThread(audioTask);
    audioThread.join();

    return 0;
}

the make command return this:

make: *** [makefile:31: run] Error -1073741819

Can you tell me where I'm going wrong and what I should do? the ASIO doc is not very user friendly...

My configuration is as follows:
OS: Window 11
compiler: g++ (MinGW64)
compile with: handmade makefile
c++ version: 23
compiler flags: -Wall -Wextra -Wpedantic

I'm trying to include other headers, I can't find another topic on this. I also ask chatGPT but it's complicated to get the right code.

Answer 1

I found the solution, to load an ASIO driver you must:

• include asio.h, asiodrivers.h
• dynamically allocate a new instance of AsioDrivers in the asioDrivers pointer
• Then get the number of devices
• get devices names with functions like:
  asioDrivers->getDriverNames(char **names, long maxDrivers)
  or a for loop as in my code below
• Then call asioDrivers->loadDriver(char *name) with a name taken from the list of devices just before
• Finally, DON'T FORGOT TO DELETE THE POINTER

#include <iostream>
#include <thread>
#include <string>
#include <vector>

#include "asio.h"
#include "asiodrivers.h"

extern AsioDrivers *asioDrivers;

void audioTask(void)
{
    asioDrivers = new AsioDrivers();

    //get number of devices
    long deviceCount { asioDrivers->asioGetNumDev() };

    //create a array of 32-char strings 
    std::vector<std::string> devicesNames(deviceCount, std::string(32, '\0'));

    //print the index and name of each device
    for(std::size_t i {0}; i < devicesNames.size(); ++i)
    {
        asioDrivers->asioGetDriverName(i, devicesNames[i].data(), 32);

        std::cout << '[' << i << "]: " << devicesNames[i] << std::endl;
    }
    
    //select a device and load it
    int index;
    std::cin >> index;
    asioDrivers->loadDriver(devicesNames[index].data());

    delete asioDrivers;
}

int main(void)
{
    std::thread audioThread(audioTask);
    audioThread.join();

    return 0;
}