Question

请查看以下代码，该代码经过编码以获取连接的USB设备列表

#include <lusb0_usb.h>
#include <iostream>

using namespace std;

int main()
{
    usb_init();
    usb_find_busses();
    usb_find_devices();

    struct usb_bus *busses = usb_get_busses();
    struct usb_bus *bus;
    struct usb_device *dev;


    for(bus=busses;bus;bus=bus->next)
    {
        for(dev=bus->devices;dev;dev->next)
        {
            cout << dev->descriptor.iProduct << endl;
        }
    }
}

当我运行此代码时，我得到了

Starting C:\Users\yohan\Documents\QTPeojects\USB-build-Desktop_Qt_5_0_0_beta2_MSVC2010_32bit_SDK-Release\release\USB.exe...
C:\Users\yohan\Documents\QTPeojects\USB-build-Desktop_Qt_5_0_0_beta2_MSVC2010_32bit_SDK-Release\release\USB.exe exited with code 0

我相信我错误地完成了这段代码。我怎么能纠正这个？

Answer 1

它可能正常运行。您需要暂停控制台以便查看输出。

尝试添加

#include <conio.h> 

_getch();

或使用其他技术暂停并等待用户输入。

Answer 2

以下代码适用于Objective-C：

libusb_device **devs; //pointer to pointer of device, used to retrieve a list of devices
ssize_t cnt; //holding number of devices in list
//libusb_set_debug(ctx, 3); //set verbosity level to 3, as suggested in the documentation
cnt = libusb_get_device_list(ctx, &devs); //get the list of devices
if(cnt < 0) {
    return false;
    //there was an error
}
//print total number of usb devices
ssize_t i; //for iterating through the list
for(i = 0; i < cnt; i++) {
    struct libusb_device_descriptor desc;
    if (libusb_get_device_descriptor(devs[i], &desc) >= 0) {
        if ((desc.idVendor == 0x04D8) && (desc.idProduct == 0x0204)){
            libusb_free_device_list(devs, 1);
            return true;
        }
    }
}
libusb_free_device_list(devs, 1); //free the list, unref the devices in it

return false;

我认为你需要改为“descriptor.i d 产品”。

如何打印已连接设备的列表

2 个答案: