FindFirstFileExW function (fileapi.h)
Searches a directory for a file or subdirectory with a name and attributes that match those specified.
For the most basic version of this function, see FindFirstFile.
To perform this operation as a transacted operation, use the FindFirstFileTransacted function.
Syntax
HANDLE FindFirstFileExW(
[in] LPCWSTR lpFileName,
[in] FINDEX_INFO_LEVELS fInfoLevelId,
[out] LPVOID lpFindFileData,
[in] FINDEX_SEARCH_OPS fSearchOp,
LPVOID lpSearchFilter,
[in] DWORD dwAdditionalFlags
);
Parameters
[in] lpFileName
The directory or path, and the file name. The file name can include wildcard characters, for example, an asterisk (*) or a question mark (?).
This parameter should not be NULL, an invalid string (for example, an empty string or a string that is missing the terminating null character), or end in a trailing backslash (\).
If the string ends with a wildcard, period, or directory name, the user must have access to the root and all subdirectories on the path.
In the of this function, the name is limited to MAX_PATH characters. To extend this limit to approximately 32,000 wide characters, call the Unicode version of the function (FindFirstFileExW), and prepend "\\?\" to the path. For more information, see Naming a File.
[in] fInfoLevelId
The information level of the returned data.
This parameter is one of the FINDEX_INFO_LEVELS enumeration values.
[out] lpFindFileData
A pointer to the buffer that receives the file data.
The pointer type is determined by the level of information that is specified in the fInfoLevelId parameter.
[in] fSearchOp
The type of filtering to perform that is different from wildcard matching.
This parameter is one of the FINDEX_SEARCH_OPS enumeration values.
lpSearchFilter
A pointer to the search criteria if the specified fSearchOp needs structured search information.
At this time, none of the supported fSearchOp values require extended search information. Therefore, this pointer must be NULL.
[in] dwAdditionalFlags
Specifies additional flags that control the search.
Return value
If the function succeeds, the return value is a search handle used in a subsequent call to FindNextFile or FindClose, and the lpFindFileData parameter contains information about the first file or directory found.
If the function fails or fails to locate files from the search string in the lpFileName parameter, the return value is INVALID_HANDLE_VALUE and the contents of lpFindFileData are indeterminate. To get extended error information, call the GetLastError function.
Remarks
The FindFirstFileEx function opens a search handle and returns information about the first file that the file system finds with a name that matches the specified pattern. This may or may not be the first file or directory that appears in a directory-listing application (such as the dir command) when given the same file name string pattern. This is because FindFirstFileEx does no sorting of the search results. For additional information, see FindNextFile.
The following list identifies some other search characteristics:
- The search is performed strictly on the name of the file, not on any attributes such as a date or a file type.
- The search includes the long and short file names.
- An attempt to open a search with a trailing backslash always fails.
- Passing an invalid string, NULL, or empty string for the lpFileName parameter is not a valid use of this function. Results in this case are undefined.
After the search handle is established, use it in the FindNextFile function to search for other files that match the same pattern with the same filtering that is being performed. When the search handle is not needed, it should be closed by using the FindClose function.
As stated previously, you cannot use a trailing backslash (\) in the lpFileName input string for FindFirstFileEx, therefore it may not be obvious how to search root directories. If you want to see files or get the attributes of a root directory, the following options would apply:
- To examine files in a root directory, you can use "C:\*" and step through the directory by using FindNextFile.
- To get the attributes of a root directory, use the GetFileAttributes function.
On network shares, you can use an lpFileName in the form of the following: "\\server\service\*". However, you cannot use an lpFileName that points to the share itself; for example, "\\server\service" is not valid.
To examine a directory that is not a root directory, use the path to that directory, without a trailing backslash. For example, an argument of "C:\Windows" returns information about the directory "C:\Windows", not about a directory or file in "C:\Windows". To examine the files and directories in "C:\Windows", use an lpFileName of "C:\Windows\*".
The following call:
FindFirstFileEx( lpFileName,
FindExInfoStandard,
lpFindData,
FindExSearchNameMatch,
NULL,
0 );
Is equivalent to the following call:
FindFirstFile( lpFileName, lpFindData );
Be aware that some other thread or process could create or delete a file with this name between the time you query for the result and the time you act on the information. If this is a potential concern for your application, one possible solution is to use the CreateFile function with CREATE_NEW (which fails if the file exists) or OPEN_EXISTING (which fails if the file does not exist).
If you are writing a 32-bit application to list all the files in a directory and the application may be run on a 64-bit computer, you should call Wow64DisableWow64FsRedirection before calling FindFirstFileEx and call Wow64RevertWow64FsRedirection after the last call to FindNextFile. For more information, see File System Redirector.
If the path points to a symbolic link, the WIN32_FIND_DATA buffer contains information about the symbolic link, not the target.
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 code shows a minimal use of FindFirstFileEx. This program is equivalent to the example in the FindFirstFile topic.
#include <windows.h>
#include <tchar.h>
#include <stdio.h>
void _tmain(int argc, TCHAR *argv[])
{
WIN32_FIND_DATA FindFileData;
HANDLE hFind;
if( argc != 2 )
{
_tprintf(TEXT("Usage: %s [target_file]\n"), argv[0]);
return;
}
_tprintf (TEXT("Target file is %s\n"), argv[1]);
hFind = FindFirstFileEx(argv[1], FindExInfoStandard, &FindFileData,
FindExSearchNameMatch, NULL, 0);
if (hFind == INVALID_HANDLE_VALUE)
{
printf ("FindFirstFileEx failed (%d)\n", GetLastError());
return;
}
else
{
_tprintf (TEXT("The first file found is %s\n"),
FindFileData.cFileName);
FindClose(hFind);
}
}
Note
The fileapi.h header defines FindFirstFileEx as an alias which 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 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 XP [desktop apps | UWP apps] |
| Minimum supported server | Windows Server 2003 [desktop apps | UWP apps] |
| Target Platform | Windows |
| Header | fileapi.h (include Windows.h) |
| Library | Kernel32.lib |
| DLL | Kernel32.dll |