#define B_CUR_DRIVER_API_VERSION N

The B_CUR_DRIVER_API_VERSION constant indicates what version of the driver API your driver will be built to.

See also: "Symbols Drivers Export"

typedef struct {
    uint32 bytes_per_sector;
    uint32 sectors_per_track;
    uint32 cylinder_count;
    uint32 head_count;
    uchar device_type;
    bool removable;
    bool read_only;
    bool write_once;
} device_geometry

The device_geometry structure is returned by the B_GET_GEOMETRY driver control function. Its fields are:

If you need to compute the total size of the device in bytes, you can obtain this figure using the following simple formula:

disk_size = geometry.cylinder_count * geometry.sectors_per_track *
geometry.head_count * geometry.bytes_per_sector;

The device type returned in device_type is one of:

typedef struct {
    device_open_hook open;
    device_close_hook close;
    device_free_hook free;
    device_control_hook control;
    device_read_hook read;
    device_write_hook write;
    device_select_hook select;
    device_deselect_hook deselect;
    device_readv_hook readv;
    device_writev_hook writev;
} device_hooks

This structure is used by device drivers to export their function hooks to the kernel.

typedef struct {
    int32 icon_size;
    void*icon_data;
} device_icon

When you want to obtain an icon for a specific device, call ioctl() on the open device, specifying the B_GET_ICON opcode. Pass in data a pointer to a device_icon structure in which icon_size indicates the size of icon you want and icon_data points to a buffer large enough to receive the icon's data.

icon_size can be either B_MINI_ICON, in which case the buffer pointed to by icon_data should be large enough to receive a 16x16 8-bit bitmap (256-byte), or B_LARGE_ICON, in which case the buffer should be large enough to receive a 32x32 8-bit bitmap (1024-byte). The most obvious way to set up this buffer would be to create a BBitmap of the appropriate size and color depth and use its buffer, like this:

BBitmap bits(BRect(0, 0, B_MINI_ICON-1, B_MINI_ICON-1, 0, B_CMAP8));
device_icon iconrec;

iconrec.icon_size = B_MINI_ICON;
iconrec.icon_data = bits.Bits();
status_t err = ioctl(dev_fd, B_GET_ICON, &iconrec);

if (err == B_OK) {
   /* enjoy the icon */
   ...
   view->DrawBitmap(bits);
} else {
   /* I don't like icons anyway */
}

typedef char driver_path[256];

Used by the B_GET_DRIVER_FOR_DEVICE control function to return the pathname of the specified device.

typedef struct {
    uint32 cookie;
    char device[256];
} open_device_iterator

Used by the B_GET_NEXT_OPEN_DEVICE control function. The first time you call this function, your open_device_iterator should have cookie initialized to 0. Then just keep calling it over and over; each time you'll get the name of the next open device. When an error is returned, you're done.

typedef struct {
    off_t offset;
    off_t size;
    int32 logical_block_size;
    int32 session;
    int32 partition;
    char device[256];
} partition_info

The partition_info structure describes a disk partition, and is used by the B_GET_PARTITION_INFO and B_SET_PARTITION control commands.

The fields are: