#ifndef _NTIOAPI_H

/**
 * Creates an empty I/O completion port. This native call neither accepts nor
 * associates a file handle; file association is a separate operation. It can also
 * be used as a packet queue without issuing file I/O.
 *
 * \param[out] IoCompletionHandle Receives a caller-owned handle; close with NtClose.
 * \param[in] DesiredAccess Requested access. IO_COMPLETION_QUERY_STATE (0x1)
 * permits depth queries; IO_COMPLETION_MODIFY_STATE (0x2) permits posting/removing.
 * \param[in, optional] ObjectAttributes Optional name, root directory and security attributes.
 * \param[in] NumberOfConcurrentThreads Concurrency limit for active queue consumers,
 * not a packet-capacity limit. Zero selects the active processor count; on x64
 * KeInitializeQueue queries all processor groups (0xFFFF).
 * \return STATUS_SUCCESS for a new port. OBJ_OPENIF can return
 * STATUS_OBJECT_NAME_EXISTS for an existing named port without clearing its queue
 * or replacing its concurrency setting.
 * \sa https://learn.microsoft.com/en-us/windows/win32/fileio/createiocompletionport
 */
_Kernel_entry_
NTSYSCALLAPI
NTSTATUS
NTAPI
NtCreateIoCompletion(
    _Out_ PHANDLE IoCompletionHandle,
    _In_ ACCESS_MASK DesiredAccess,
    _In_opt_ PCOBJECT_ATTRIBUTES ObjectAttributes,
    _In_opt_ ULONG NumberOfConcurrentThreads
    );

#endif
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#ifndef _NTZWAPI_H

_Kernel_entry_
NTSYSCALLAPI
NTSTATUS
NTAPI
ZwCreateIoCompletion(
    _Out_ PHANDLE IoCompletionHandle,
    _In_ ACCESS_MASK DesiredAccess,
    _In_opt_ PCOBJECT_ATTRIBUTES ObjectAttributes,
    _In_opt_ ULONG NumberOfConcurrentThreads
    );

#endif
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