User's Manual

ProgrammingChapter —7
254 700 Series Color Mob ile Computer User’s Manual
IOCTL_HAL_GET_DEVICEID
This IOCTL returns the device ID. There are two types of device IDs
supported,whicharedifferentiatedbasedonthesizeoftheoutput buffer.
TheUUIDisreturnedifthebuffersizeissetto
sizeof(UNIQUE_DEVICEID),otherwisetheoldstyledeviceIDisre-
turned.
Usage
#include “pkfuncs.h”
#include “deviceid.h”
Syntax
BOOL KernelIoControl( IOCTL_HAL_GET_DEVICEID,LPVOID
lpInBuf,DWORD nInBufSize,LPVOID lpOutBuf,DWORD
nOutBufSize,LPDWORD lpBytesReturned );
Parameters
lpInBuf Should be set to NULL. STRICT_ID settings are not supported.
lpInBufSize Should be set to zero.
lpOutBuf Must point to a UNIQUE_DEVICEID structure as defined by
DEVICEID.H if the UUID is to be returned
nOutBufSize The size of the UNIQUE_DEVICEID in bytes if the UUID is to
be returned. A DEVICE_ID as defined by PKFUNCS.H is re-
turned if the size in bytes is greater than or equal to sizeof(DE-
VICE_ID).
lpBytesReturned The number of bytes returne d by the function.
Return Values
Returns TRUE if function succeeds. Returns FALSE if the function fails.
GetLastError() may be used to get the extended error value.