#ifndef _NTIOAPI_H

/**
 * The NtCancelIoFileEx routine marks any outstanding I/O operations for the specified file handle.
 *
 * \param[in] FileHandle Handle to the file.
 * \param[in, optional] IoRequestToCancel Pointer to an IO_STATUS_BLOCK structure that identifies the I/O request to cancel.
 * \param[out] IoStatusBlock Pointer to an IO_STATUS_BLOCK structure.
 * \return NTSTATUS Successful or errant status.
 * \sa https://learn.microsoft.com/en-us/windows/win32/api/ioapiset/nf-ioapiet-cancelioex
 * \remarks A non-NULL IoRequestToCancel identifies the original request by its IO_STATUS_BLOCK address; NULL selects
 * matching requests without that address filter. The helper searches the current process's file and
 * thread request lists and returns STATUS_NOT_FOUND when nothing matches. Cancellation can race normal
 * completion: retain the original request buffers and status block until that request's completion is
 * observed. The separate cancellation IoStatusBlock has Information = 0, not a count of canceled requests.
 */
_Kernel_entry_
NTSYSCALLAPI
NTSTATUS
NTAPI
NtCancelIoFileEx(
    _In_ HANDLE FileHandle,
    _In_opt_ PIO_STATUS_BLOCK IoRequestToCancel,
    _Out_ PIO_STATUS_BLOCK IoStatusBlock
    );

#endif
View code on GitHub

#ifndef _NTZWAPI_H

_Kernel_entry_
NTSYSCALLAPI
NTSTATUS
NTAPI
ZwCancelIoFileEx(
    _In_ HANDLE FileHandle,
    _In_opt_ PIO_STATUS_BLOCK IoRequestToCancel,
    _Out_ PIO_STATUS_BLOCK IoStatusBlock
    );

#endif
View code on GitHub