GetFullPathNameA function (fileapi.h)
Retrieves the full path and file name of the specified file.
To perform this operation as a transacted operation, use the GetFullPathNameTransacted function.
For more information about file and path names, see File Names, Paths, and Namespaces.
Syntax
DWORD GetFullPathNameA(
[in] LPCSTR lpFileName,
[in] DWORD nBufferLength,
[out] LPSTR lpBuffer,
[out] LPSTR *lpFilePart
);
Parameters
[in] lpFileName
The name of the file.
This parameter can be a short (the 8.3 form) or long file name. This string can also be a share or volume name.
[in] nBufferLength
The size of the buffer to receive the null-terminated string for the drive and path, in TCHARs.
[out] lpBuffer
A pointer to a buffer that receives the null-terminated string for the drive and path.
[out] lpFilePart
A pointer to a buffer that receives the address (within lpBuffer) of the final file name component in the path.
This parameter can be NULL.
If lpBuffer refers to a directory and not a file, lpFilePart receives zero.
Return value
If the function succeeds, the return value is the length, in TCHARs, of the string copied to lpBuffer, not including the terminating null character.
If the lpBuffer buffer is too small to contain the path, the return value is the size, in TCHARs, of the buffer that is required to hold the path and the terminating null character.
If the function fails for any other reason, the return value is zero. To get extended error information, call GetLastError.
Remarks
GetFullPathName merges the name of the current drive and directory with a specified file name to determine the full path and file name of a specified file. It also calculates the address of the file name portion of the full path and file name.
This function does not verify that the resulting path and file name are valid, or that they see an existing file on the associated volume.
Note that the lpFilePart parameter does not require string buffer space, but only enough for a single address. This is because it simply returns an address within the buffer that already exists for lpBuffer.
Share and volume names are valid input for lpFileName. For example, the following list identities the returned path and file names if test-2 is a remote computer and U: is a network mapped drive whose current directory is the root of the volume:
- If you specify "\\test-2\q$\lh" the path returned is "\\test-2\q$\lh"
- If you specify "\\?\UNC\test-2\q$\lh" the path returned is "\\?\UNC\test-2\q$\lh"
- If you specify "U:" the path returned is the current directory on the "U:\" drive
If the return value is greater than or equal to the value specified in nBufferLength, you can call the function again with a buffer that is large enough to hold the path. For an example of this case in addition to using zero-length buffer for dynamic allocation, see the Example Code section.
Relative paths passed to the GetFullPathName function are interpreted as relative to the process's current directory. The current directory state written by the SetCurrentDirectory function is global to the process and can be changed by any thread at any time. Applications should be aware that consecutive calls to the GetFullPathName function with a relative path may produce different results if the current directory changes between the two calls.
To avoid problems caused by inconsistent results, multithreaded applications and shared library code should avoid using relative paths. If a relative path is received, it should be consumed exactly once, either by passing the relative path directly to a function like CreateFile, or by converting it to an absolute path and using the absolute path from that point forward.
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 a basic use of GetFullPathName, GetLongPathName, and GetShortPathName. For another example using dynamic allocation, see GetShortPathName.
#include <windows.h>
#include <tchar.h>
#include <stdio.h>
#define BUFSIZE 4096
#define LONG_DIR_NAME TEXT("c:\\longdirectoryname")
void _tmain(int argc, TCHAR *argv[])
{
DWORD retval=0;
BOOL success;
TCHAR buffer[BUFSIZE]=TEXT("");
TCHAR buf[BUFSIZE]=TEXT("");
TCHAR** lppPart={NULL};
if( argc != 2 )
{
_tprintf(TEXT("Usage: %s [file]\n"), argv[0]);
return;
}
// Retrieve the full path name for a file.
// The file does not need to exist.
retval = GetFullPathName(argv[1],
BUFSIZE,
buffer,
lppPart);
if (retval == 0)
{
// Handle an error condition.
printf ("GetFullPathName failed (%d)\n", GetLastError());
return;
}
else
{
_tprintf(TEXT("The full path name is: %s\n"), buffer);
if (lppPart != NULL && *lppPart != 0)
{
_tprintf(TEXT("The final component in the path name is: %s\n"), *lppPart);
}
}
// Create a long directory name for use with the next two examples.
success = CreateDirectory(LONG_DIR_NAME,
NULL);
if (!success)
{
// Handle an error condition.
printf ("CreateDirectory failed (%d)\n", GetLastError());
return;
}
// Retrieve the short path name.
retval = GetShortPathName(LONG_DIR_NAME,
buf,
BUFSIZE);
if (retval == 0)
{
// Handle an error condition.
printf ("GetShortPathName failed (%d)\n", GetLastError());
return;
}
else _tprintf(TEXT("The short name for %s is %s\n"),
LONG_DIR_NAME, buf);
// Retrieve the long path name.
retval = GetLongPathName(buf,
buffer,
BUFSIZE);
if (retval == 0)
{
// Handle an error condition.
printf ("GetLongPathName failed (%d)\n", GetLastError());
return;
}
else _tprintf(TEXT("The long name for %s is %s\n"), buf, buffer);
// Clean up the directory.
success = RemoveDirectory(LONG_DIR_NAME);
if (!success)
{
// Handle an error condition.
printf ("RemoveDirectory failed (%d)\n", GetLastError());
return;
}
}
Note
The fileapi.h header defines GetFullPathName 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 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 |