Lucent Technologies USS-720 manual 5 I/O Control Data Structures, Deviceinstanceheader, February

Preliminary User Guide, Rev. 2	USS-720
February 1999	USB Device Driver

5 I/O Control Data Structures

This section describes the data structures used in I/O control codes.

5.1 DEVICE_INSTANCE_HEADER

The DEVICE_INSTANCE_HEADER structure is used when issuing the IOCTL_GET_DEVICE_INSTANCES con- trol code.

5.1.1 Data Structure

typedef struct _DEVICE_INSTANCE_HEADER{ DWORD NumDeviceInstance; DWORD TotalLength;

}DEVICE_INSTANCE_HEADER;

5.1.2 Members

NumDeviceInstance—Total number of device instances.

TotalLength—Total length (in bytes) of device instances including the header.

5.2 DEVICE_INSTANCE

The DEVICE_INSTANCE structure is used when issuing the IOCTL_GET_DEVICE_INSTANCES control code.

5.2.1 Data Structure

typedef struct _DEVICE_INSTANCE{ DWORD InstanceIndex; DWORD LinkNameLength;

CHAR DeviceLinkName[64];

}DEVICE_INSTANCE, *PDEVICE_INSTANCE;

5.2.2 Members

InstanceIndex—Index of this instance.

LinkNameLength—Length (in bytes) of the DeviceLinkName.

DeviceLinkName—Pointer to a null terminated string containing the symbolic link name of a device instance.

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