linux下获取设备的bus和device编号C++

要在Linux下获取设备的bus和device编号，可以使用libudev库，以下是示例C++代码：

#include <iostream>
#include <libudev.h>

int main() {
    struct udev *udev = udev_new();
    if (!udev) {
        std::cerr << "Failed to create udev context" << std::endl;
        return 1;
    }

    struct udev_enumerate *enumerate = udev_enumerate_new(udev);
    if (!enumerate) {
        std::cerr << "Failed to create udev enumerate context" << std::endl;
        udev_unref(udev);
        return 1;
    }

    udev_enumerate_add_match_subsystem(enumerate, "usb");
    udev_enumerate_scan_devices(enumerate);

    struct udev_list_entry *devices = udev_enumerate_get_list_entry(enumerate);
    struct udev_list_entry *entry;

    udev_list_entry_foreach(entry, devices) {
        const char *path = udev_list_entry_get_name(entry);
        struct udev_device *dev = udev_device_new_from_syspath(udev, path);
        if (!dev) {
            std::cerr << "Failed to create udev device context" << std::endl;
            continue;
        }

        const char *bus = udev_device_get_property_value(dev, "ID_BUS");
        const char *device = udev_device_get_property_value(dev, "ID_SERIAL_SHORT");

        std::cout << "Bus: " << bus << ", Device: " << device << std::endl;

        udev_device_unref(dev);
    }

    udev_enumerate_unref(enumerate);
    udev_unref(udev);

    return 0;
}

这段代码会列出所有USB设备的bus和device编号。你可以根据需要修改`udev_enumerate_add_match_subsystem`函数的参数，来获取其他类型的设备的信息。