IO_SESSION_EVENT - NtDoc

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

// Sessions

typedef enum _IO_SESSION_EVENT
{
    IoSessionEventIgnore,
    IoSessionEventCreated,
    IoSessionEventTerminated,
    IoSessionEventConnected,
    IoSessionEventDisconnected,
    IoSessionEventLogon,
    IoSessionEventLogoff,
    IoSessionEventMax
} IO_SESSION_EVENT;

#endif

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This enumeration is documented in Windows Driver Kit.