#ifndef _NTIOAPI_H
// Output structure for IOCTL_MOUNTMGR_NEXT_DRIVE_LETTER.
typedef struct _MOUNTMGR_DRIVE_LETTER_INFORMATION
{
BOOLEAN DriveLetterWasAssigned;
UCHAR CurrentDriveLetter;
} MOUNTMGR_DRIVE_LETTER_INFORMATION, *PMOUNTMGR_DRIVE_LETTER_INFORMATION;
View code on GitHub
This structure is documented in Windows Driver Kit.