IOCTL_MOUNTMGR_CHANGE_NOTIFY - NtDoc

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

#define IOCTL_MOUNTMGR_CHANGE_NOTIFY                CTL_CODE(MOUNTMGRCONTROLTYPE, 8, METHOD_BUFFERED, FILE_READ_ACCESS)

#endif

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This IOCTL is documented in Windows Driver Kit.