FsRtlGetPerStreamContextPointer macro (ntifs.h)

Article
02/22/2024

The FsRtlGetPerStreamContextPointer macro returns the file system's stream context for a file stream.

Syntax

void FsRtlGetPerStreamContextPointer(
   _fo
);

Parameters

_fo

Pointer to a file object for the file stream.

Return value

None

Remarks

File system filter drivers can use the FsRtlGetPerStreamContextPointer macro to obtain a stream context pointer for the file stream that is represented by a given file object. A stream context pointer is a pointer to the file system's stream context for the file stream. This pointer can be passed as a parameter to FsRtlInsertPerStreamContext, FsRtlLookupPerStreamContext, and FsRtlRemovePerStreamContext.

The stream context pointer points to a FSRTL_ADVANCED_FCB_HEADER structure that uniquely identifies the file stream to the file system. This structure is usually embedded in a stream context object, such as a file control block (FCB) or stream control block (SCB). When the file stream is opened, the file system stores a pointer to the FCB or SCB in the file object's FsContext member.

Note The FsRtlGetPerStreamContextPointer macro can only be used on file systems that support advanced FCB headers.

For more information, see Tracking Per-Stream Context in a Legacy File System Filter Driver.

Requirements

Requirement	Value
Minimum supported client	Windows XP; Windows 2000 SP4 Update Rollup
Target Platform	Desktop
Header	ntifs.h (include Ntifs.h)
IRQL	<= APC_LEVEL