GetFinalPathNameByHandleA function (fileapi.h)

Article
02/09/2023

Retrieves the final path for the specified file.

For more information about file and path names, see Naming a File.

Syntax

DWORD GetFinalPathNameByHandleA(
  [in]  HANDLE hFile,
  [out] LPSTR  lpszFilePath,
  [in]  DWORD  cchFilePath,
  [in]  DWORD  dwFlags
);

Parameters

[in] hFile

A handle to a file or directory.

[out] lpszFilePath

A pointer to a buffer that receives the path of hFile.

[in] cchFilePath

The size of lpszFilePath, in TCHARs. This value must include a NULL termination character.

[in] dwFlags

The type of result to return. This parameter can be one of the following values.

Value	Meaning
FILE_NAME_NORMALIZED 0x0	Return the normalized drive name. This is the default.
FILE_NAME_OPENED 0x8	Return the opened file name (not normalized).

This parameter can also include one of the following values.

Value	Meaning
VOLUME_NAME_DOS 0x0	Return the path with the drive letter. This is the default.
VOLUME_NAME_GUID 0x1	Return the path with a volume GUID path instead of the drive name.
VOLUME_NAME_NONE 0x4	Return the path with no drive information.
VOLUME_NAME_NT 0x2	Return the path with the volume device path.

Return value

If the function succeeds, the return value is the length of the string received by lpszFilePath, in TCHARs. This value does not include the size of the terminating null character.

Windows Server 2008 and Windows Vista: For the ANSI version of this function, GetFinalPathNameByHandleA, the return value includes the size of the terminating null character.

If the function fails because lpszFilePath is too small to hold the string plus the terminating null character, the return value is the required buffer size, in TCHARs. This value includes the size of the terminating null character.

If the function fails for any other reason, the return value is zero. To get extended error information, call GetLastError.

Return code	Description
ERROR_PATH_NOT_FOUND	Can be returned if you are searching for a drive letter and one does not exist. For example, the handle was opened on a drive that is not currently mounted, or if you create a volume and do not assign it a drive letter. If a volume has no drive letter, you can use the volume GUID path to identify it. This return value can also be returned if you are searching for a volume GUID path on a network share. Volume GUID paths are not created for network shares.
ERROR_NOT_ENOUGH_MEMORY	Insufficient memory to complete the operation.
ERROR_INVALID_PARAMETER	Invalid flags were specified for dwFlags.

Remarks

The Server Message Block (SMB) Protocol does not support queries for normalized paths. Consequently, when you call this function passing the handle of a file opened using SMB, and with the FILE_NAME_NORMALIZED flag, the function splits the path into its components and tries to query for the normalized name of each of those components in turn. If the user lacks access permission to any one of those components, then the function call fails with ERROR_ACCESS_DENIED.

A final path is the path that is returned when a path is fully resolved. For example, for a symbolic link named "C:\tmp\mydir" that points to "D:\yourdir", the final path would be "D:\yourdir".

The string that is returned by this function uses the "\\?\" syntax. For more information, see CreateFile.

In Windows 8 and Windows Server 2012, this function is supported by the following technologies.

Technology	Supported
Server Message Block (SMB) 3.0 protocol	Yes
SMB 3.0 Transparent Failover (TFO)	Yes
SMB 3.0 with Scale-out File Shares (SO)	Yes
Cluster Shared Volume File System (CsvFS)	Yes
Resilient File System (ReFS)	Yes

Examples

The following example demonstrates the use of the GetFinalPathNameByHandle function.

#include <windows.h>
#include <tchar.h>
#include <stdio.h>

#define BUFSIZE MAX_PATH

void __cdecl _tmain(int argc, TCHAR *argv[])
{
    TCHAR Path[BUFSIZE];
    HANDLE hFile;
    DWORD dwRet;

    printf("\n");
    if( argc != 2 )
    {
        printf("ERROR:\tIncorrect number of arguments\n\n");
        printf("%s <file_name>\n", argv[0]);
        return;
    }

    hFile = CreateFile(argv[1],               // file to open
                       GENERIC_READ,          // open for reading
                       FILE_SHARE_READ,       // share for reading
                       NULL,                  // default security
                       OPEN_EXISTING,         // existing file only
                       FILE_ATTRIBUTE_NORMAL, // normal file
                       NULL);                 // no attr. template

    if( hFile == INVALID_HANDLE_VALUE)
    {
        printf("Could not open file (error %d\n)", GetLastError());
        return;
    }

    dwRet = GetFinalPathNameByHandle( hFile, Path, BUFSIZE, VOLUME_NAME_NT );
    if(dwRet < BUFSIZE)
    {
        _tprintf(TEXT("\nThe final path is: %s\n"), Path);
    }
    else printf("\nThe required buffer size is %d.\n", dwRet);

    CloseHandle(hFile);
}

Note

The fileapi.h header defines GetFinalPathNameByHandle as an alias that automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that is not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.

Requirements

Requirement	Value
Minimum supported client	Windows Vista [desktop apps \| UWP apps]
Minimum supported server	Windows Server 2008 [desktop apps \| UWP apps]
Target Platform	Windows
Header	fileapi.h (include Windows.h)
Library	Kernel32.lib
DLL	Kernel32.dll

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