FindFirstFileW function (fileapi.h)
Searches a directory for a file or subdirectory with a name that matches a specific name (or partial name if wildcards are used).
To specify additional attributes to use in a search, use the FindFirstFileEx function.
To perform this operation as a transacted operation, use the FindFirstFileTransacted function.
Syntax
HANDLE FindFirstFileW(
[in] LPCWSTR lpFileName,
[out] LPWIN32_FIND_DATAW lpFindFileData
);
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 permissions to the root and all subdirectories on the path.
By default, the name is limited to MAX_PATH characters. To extend this limit to 32,767 wide characters, prepend "\\?\" to the path. For more information, see Naming Files, Paths, and Namespaces.
Tip
Starting with Windows 10, Version 1607, you can opt-in to remove the MAX_PATH limitation without prepending "\\?\". See the "Maximum Path Length Limitation" section of Naming Files, Paths, and Namespaces for details.
[out] lpFindFileData
A pointer to the WIN32_FIND_DATA structure that receives information about a found file or directory.
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.
If the function fails because no matching files can be found, the GetLastError function returns ERROR_FILE_NOT_FOUND.
Remarks
The FindFirstFile 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 FindFirstFile 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 (for other options, see FindFirstFileEx).
- 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.
When the search handle is no longer needed, close it by using the FindClose function, not CloseHandle.
As stated previously, you cannot use a trailing backslash (\) in the lpFileName input string for FindFirstFile, 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\Share\*". However, you cannot use an lpFileName that points to the share itself; for example, "\\Server\Share" 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\*".
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 the Wow64DisableWow64FsRedirection function before calling FindFirstFile 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 C++ example shows you a minimal use of FindFirstFile.
#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 = FindFirstFile(argv[1], &FindFileData);
if (hFind == INVALID_HANDLE_VALUE)
{
printf ("FindFirstFile failed (%d)\n", GetLastError());
return;
}
else
{
_tprintf (TEXT("The first file found is %s\n"),
FindFileData.cFileName);
FindClose(hFind);
}
}
For another example, see Listing the Files in a Directory.
Note
The fileapi.h header defines FindFirstFile 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 |