Lucent Technologies USS-720 manual Ioctlgetcapabilities, 4 I/O Control Codes continued, February

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

4 I/O Control Codes (continued)

4.10 IOCTL_GET_CAPABILITIES

IOCTL_GET_CAPABILITIES returns a variable buffer length containing the device capabilities string. This is an IEEE 1284 compatible string. Details regarding parameters and error codes follow.

4.10.1 Parameters

lpInBuffer—Points to an input buffer. Not used with this operation. Set to NULL.

nInBufferSize—Specifies the size (in bytes) of the buffer pointed to by lpInBuffer. Not used with this operation. Set to zero.

lpOutBuffer—Points to an output buffer that will receive an IEEE 1284 Device ID string.

nOutBufferSize—Specifies the size (in bytes) of the buffer pointed to by lpOutBuffer. Specify zero to return only the length of the Device ID string in lpBytesReturned.

lpBytesReturned—Points to a DWORD that receives the actual size (in bytes) of the data stored into lpOutBuffer or returns the length of the Device ID string if nOutBufferSize is zero.

4.10.2 Notes

None.

4.10.3 Error Codes

ERROR_NOT_ENOUGH_BUFFER—lpOutBuffer was not large enough to receive the Device ID string (see USS- 720 USB-to-IEEE 1284 Bridge Preliminary Data Sheet, “Printer Class-Specific Requests”).

STATUS_INSUFFICIENT_RESOURCES—Not enough memory to perform the request on this device instance.

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