Question

V4L2的USB摄像头编程，用的是友善之臂的MINI6410，但是程序只对有驱摄像头好用，现在的无驱摄像头不好用

那位可以指点一下：
fd = open(CAMERA_DEVICE, O_RDWR, 0);
if (fd < 0) {
return -1;
}
struct v4l2_capability cap;
ret = ioctl(fd, VIDIOC_QUERYCAP, &cap);
if (ret < 0) {
return ret;
}
struct v4l2_format fmt;
memset(&fmt, 0, sizeof(fmt));
fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
fmt.fmt.pix.width = 240;
fmt.fmt.pix.height = 480;
fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;
fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
ret = ioctl(fd, VIDIOC_S_FMT, &fmt);
if (ret < 0) {
printf("VIDIOC_S_FMT failed (%d)\n", ret);
return ret;
}
ret = ioctl(fd, VIDIOC_G_FMT, &fmt);
if (ret < 0) {
printf("VIDIOC_G_FMT failed (%d)\n", ret);
return ret;
}
struct v4l2_requestbuffers reqbuf;
reqbuf.count = BUFFER_COUNT;
reqbuf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
reqbuf.memory = V4L2_MEMORY_MMAP;
ret = ioctl(fd , VIDIOC_REQBUFS, &reqbuf);
if(ret < 0) {
printf("VIDIOC_REQBUFS failed (%d)\n", ret);
return ret;
}
VideoBuffer* buffers = (VideoBuffer *)calloc( reqbuf.count, sizeof(*buffers) );
struct v4l2_buffer buf;
for (i = 0; i < reqbuf.count; i++)
{
buf.index = i;
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
ret = ioctl(fd , VIDIOC_QUERYBUF, &buf);
if(ret < 0) {
printf("VIDIOC_QUERYBUF (%d) failed (%d)\n", i, ret);---返回了错误！！！
return ret;
}
字数限制，我把程序精简了？

Answer 1

查询系统硬件的VID和PID，VID/PID是全球USB组织统一分配的代码，VID是代表厂家，PID 是代表产品型号，任何一个USB设备生产商必须注册此两个号码，且注册后不能修改。

多读读彩虹桥木马的源码，看人家是怎么处理的。

追问

你好，我刚刚接触Linux编程，可以说详细一点吗？