ZwQueryInformationByName function (wdm.h)
ZwQueryInformationByName returns the requested information about a file specified by file name.
Syntax
NTSYSAPI NTSTATUS ZwQueryInformationByName(
[in] POBJECT_ATTRIBUTES ObjectAttributes,
[out] PIO_STATUS_BLOCK IoStatusBlock,
[out] PVOID FileInformation,
[in] ULONG Length,
[in] FILE_INFORMATION_CLASS FileInformationClass
);
Parameters
[in] ObjectAttributes
Pointer to an OBJECT_ATTRIBUTES structure that contains the file's attributes, including file name.
[out] IoStatusBlock
Pointer an IO_STATUS_BLOCK structure containing the caller's I/O status.
[out] FileInformation
Pointer to the caller-supplied buffer in which to return the requested information about the file. The structure of the buffer is determined by the FileInformationClass parameter.
[in] Length
Length, in bytes, of the buffer that FileInformation points to.
[in] FileInformationClass
A FILE_INFORMATION_CLASS value that identifies the type of file information to return in the buffer that FileInformation points to. FileInformationClass can be one of the following values.
| FILE_INFORMATION_CLASS Value | Type of Information to Return |
|---|---|
| FileStatInformation (68) | FILE_STAT_INFORMATION. Available starting with Windows 10, version 1709. |
| FileStatLxInformation (70) | FILE_STAT_LX_INFORMATION. Available starting with Windows 10 April 2018 Update. |
| FileCaseSensitiveInformation (71) | FILE_CASE_SENSITIVE_INFORMATION. Available starting with Windows 10 April 2018 Update. |
Return value
ZwQueryInformationByName returns STATUS_SUCCESS upon successful completion; otherwise it returns an error code, such as one of the following.
| Error Code | Meaning |
|---|---|
| STATUS_INVALID_PARAMETER | The FileInformationClass parameter contains an invalid value. |
| STATUS_INFO_LENGTH_MISMATCH | The buffer size specified by Length is not large enough to contain the requested information. |
Remarks
ZwQueryInformationByName queries and returns the requested information about the file. It does so without opening the actual file, making it more efficient than ZwQueryInformationFile, which requires a file open (and subsequent file close).
Callers of ZwQueryInformationByName must be running at IRQL = PASSIVE_LEVEL and with special kernel APCs enabled.
Requirements
| Requirement | Value |
|---|---|
| Header | wdm.h |
| IRQL | PASSIVE_LEVEL (see Remarks section) |