#ifndef _NTIOAPI_H

/**
 * The NtCreateIoCompletion routine creates an I/O completion port and associates it with a specified file handle,
 * or creates an I/O completion port that is not yet associated with a file handle, allowing association at a later time.
 *
 * \param[out] IoCompletionHandle Pointer to a variable that receives a handle to the I/O completion port.
 * \param[in] DesiredAccess The requested access to the object.
 * \param[in] ObjectAttributes Pointer to an OBJECT_ATTRIBUTES structure that contains the name to an existing I/O completion port or NULL.
 * \param[out] NumberOfConcurrentThreads The maximum number of threads that the operating system can allow to concurrently process
 * I/O completion packets for the I/O completion port. This parameter is ignored if the ExistingCompletionPort parameter is not NULL.
 * If this parameter is zero, the system allows as many concurrently running threads as there are processors in the system.
 * \return NTSTATUS Successful or errant status.
 * \sa https://learn.microsoft.com/en-us/windows/win32/fileio/createiocompletionport
 */
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

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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