DEV_BROADCAST_VOLUME

The DEV_BROADCAST_VOLUME structure contains information about a logical volume.

typedef struct _DEV_BROADCAST_VOLUME {
  DWORD dbcv_size; 
  DWORD dbcv_devicetype; 
  DWORD dbcv_reserved; 
  DWORD dbcv_unitmask; 
  WORD dbcv_flags; 
} DEV_BROADCAST_VOLUME;
typedef DEV_BROADCAST_VOLUME *PDEV_BROADCAST_VOLUME;

Members

dbcv_size

Specifies the size of this structure, in bytes.

dbcv_devicetype

Set to the device type DBT_DEVTYP_VOLUME.

dbcv_reserved

Reserved; do not use.

dbcv_unitmask

A logical unit mask identifying one or more logical units. Each bit in the mask corresponds to one logical drive. Bit 0 represents drive A, bit 1 represents drive B, and so on.

dbcv_flags

Specifies whether drive or media is affected. This parameter can be one of the following flags.

Value	Meaning
DBTF_MEDIA	Change affects media in drive. If not set, change affects physical device or drive.
DBTF_NET	Indicated logical volume is a network volume.

Remarks

Although the dbcv_unitmask member may specify more than one volume in any message, this does not guarantee that only message is generated for a specified event. Multiple system components may independently generate messages for logical volumes at the same time.

Messages for media arrival and removal are sent only for media in devices that support a soft-eject mechanism. For example, applications will not see media-related volume messages for floppy disks.

Messages for network drive arrival and removal are not sent whenever network commands are issued, but rather when network connections will disappear as the result of a hardware event.

Requirements

  Windows NT/2000: Requires Windows 2000.
  Windows 95/98: Requires Windows 95 or later.
  Header: Declared in Dbt.h.

See Also

Device Management Overview, Device Management Structures, DEV_BROADCAST_HDR, WM_DEVICECHANGE