IoIsOperationSynchronous function (ntifs.h)
The IoIsOperationSynchronous routine determines whether a given IRP represents a synchronous or asynchronous I/O request.
Syntax
BOOLEAN IoIsOperationSynchronous(
[in] PIRP Irp
);
Parameters
[in] Irp
Pointer to the IRP for the operation.
Return value
IoIsOperationSynchronous returns TRUE if the operation is synchronous, otherwise FALSE.
Remarks
IoIsOperationSynchronous determines whether a given IRP requests a synchronous or asynchronous I/O operation, according to the following conditions:
If the IRP requests asynchronous paging I/O, the operation is asynchronous, even if one of the other conditions is true.
If the IRP requests synchronous paging I/O, the operation is synchronous.
If the file object was opened for synchronous I/O, the operation is synchronous.
If the IRP_SYNCHRONOUS_API flag is set in the IRP, the operation is synchronous. This flag is set for operations, such as ZwQueryInformationFile and ZwSetInformationFile, that are always synchronous, even when performed on a file object that was opened for asynchronous I/O.
If none of the above conditions is true, the operation is asynchronous.
IoIsOperationSynchronous also returns TRUE if the IRP contains an IOCTL or FSCTL request with an I/O or file system control code that was defined with METHOD_BUFFERED, even if the file object was opened for asynchronous I/O. Such a request is likely to be made synchronous by the file system, but this is not necessarily true in all cases.
Requirements
| Requirement | Value |
|---|---|
| Target Platform | Universal |
| Header | ntifs.h (include Ntifs.h) |
| Library | NtosKrnl.lib |
| DLL | NtosKrnl.exe |
| IRQL | Any level |