MOUNTMGR_DRIVE_LETTER_TARGET - NtDoc

Native API online documentation, based on the System Informer (formerly Process Hacker) phnt headers
#ifndef _NTIOAPI_H

// Input structure for IOCTL_MOUNTMGR_NEXT_DRIVE_LETTER.
typedef struct _MOUNTMGR_DRIVE_LETTER_TARGET
{
    USHORT DeviceNameLength;
    _Field_size_bytes_(DeviceNameLength) WCHAR DeviceName[1];
} MOUNTMGR_DRIVE_LETTER_TARGET, *PMOUNTMGR_DRIVE_LETTER_TARGET;

#endif

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This structure is documented in Windows Driver Kit.