ZwLockFile

function ZwLockFile(

  FileHandle: HANDLE;

  Event: HANDLE;

  ApcRoutine: PIO_APC_ROUTINE;

  ApcContext: PVOID;

  IoStatusBlock: PIO_STATUS_BLOCK;

  LockOffset: PULARGE_INTEGER;

  LockLength: PULARGE_INTEGER;

  Key: ULONG;

  FailImmediately: Boolean;

  ExclusiveLock: Boolean

):NTSTATUS;