---
description: "Learn more about: _fullpath, _wfullpath"
title: "_fullpath, _wfullpath"
ms.date: "4/2/2020"
api_name: ["_fullpath", "_wfullpath", "_o__fullpath", "_o__wfullpath"]
api_location: ["msvcrt.dll", "msvcr80.dll", "msvcr90.dll", "msvcr100.dll", "msvcr100_clr0400.dll", "msvcr110.dll", "msvcr110_clr0400.dll", "msvcr120.dll", "msvcr120_clr0400.dll", "ucrtbase.dll", "api-ms-win-crt-filesystem-l1-1-0.dll", "api-ms-win-crt-private-l1-1-0.dll"]
api_type: ["DLLExport"]
topic_type: ["apiref"]
f1_keywords: ["wfullpath", "fullpath", "_wfullpath", "_fullpath"]
helpviewer_keywords: ["_wfullpath function", "relative file paths", "absolute paths", "wfullpath function", "_fullpath function", "fullpath function"]
ms.assetid: 4161ec17-0d22-45dd-b07d-0222553afae9
---
# _fullpath, _wfullpath

Creates an absolute or full path name for the specified relative path name.

## Syntax

```C
char *_fullpath(
   char *absPath,
   const char *relPath,
   size_t maxLength
);
wchar_t *_wfullpath(
   wchar_t *absPath,
   const wchar_t *relPath,
   size_t maxLength
);
```

### Parameters

*absPath*<br/>
Pointer to a buffer containing the absolute or full path name, or **NULL**.

*relPath*<br/>
Relative path name.

*maxLength*<br/>
Maximum length of the absolute path name buffer (*absPath*). This length is in bytes for **_fullpath** but in wide characters (**`wchar_t`**) for **_wfullpath**.

## Return Value

Each of these functions returns a pointer to a buffer containing the absolute path name (*absPath*). If there is an error (for example, if the value passed in *relPath* includes a drive letter that is not valid or cannot be found, or if the length of the created absolute path name (*absPath*) is greater than *maxLength*), the function returns **NULL**.

## Remarks

The **_fullpath** function expands the relative path name in *relPath* to its fully qualified or absolute path and stores this name in *absPath*. If *absPath* is **NULL**, **malloc** is used to allocate a buffer of sufficient length to hold the path name. It is the responsibility of the caller to free this buffer. A relative path name specifies a path to another location from the current location (such as the current working directory: "."). An absolute path name is the expansion of a relative path name that states the entire path required to reach the desired location from the root of the file system. Unlike **_makepath**, **_fullpath** can be used to obtain the absolute path name for relative paths (*relPath*) that include "./" or "../" in their names.

For example, to use C run-time routines, the application must include the header files that contain the declarations for the routines. Each header file include statement references the location of the file in a relative manner (from the application's working directory):

```C
By default, this function's global state is scoped to the application. To change this, see [Global state in the CRT](../global-state.md).

#include <stdlib.h>
```

when the absolute path (actual file system location) of the file might be:

`\\machine\shareName\msvcSrc\crt\headerFiles\stdlib.h`

**_fullpath** automatically handles multibyte-character string arguments as appropriate, recognizing multibyte-character sequences according to the multibyte code page currently in use. **_wfullpath** is a wide-character version of **_fullpath**; the string arguments to **_wfullpath** are wide-character strings. **_wfullpath** and **_fullpath** behave identically except that **_wfullpath** does not handle multibyte-character strings.

If **_DEBUG** and **_CRTDBG_MAP_ALLOC** are both defined, calls to **_fullpath** and **_wfullpath** are replaced by calls to **_fullpath_dbg** and **_wfullpath_dbg** to allow for debugging memory allocations. For more information, see [_fullpath_dbg, _wfullpath_dbg](fullpath-dbg-wfullpath-dbg.md).

This function invokes the invalid parameter handler, as described in [Parameter Validation](../../c-runtime-library/parameter-validation.md), if *maxlen* is less than or equal to 0. If execution is allowed to continue, this function sets **errno** to **EINVAL** and returns **NULL**.

### Generic-Text Routine Mappings

|Tchar.h routine|_UNICODE and _MBCS not defined|_MBCS defined|_UNICODE defined|
|---------------------|--------------------------------------|--------------------|-----------------------|
|**_tfullpath**|**_fullpath**|**_fullpath**|**_wfullpath**|

If the *absPath* buffer is **NULL**, **_fullpath** calls [malloc](malloc.md) to allocate a buffer and ignores the *maxLength* argument. It is the caller's responsibility to deallocate this buffer (using [free](free.md)) as appropriate. If the *relPath* argument specifies a disk drive, the current directory of this drive is combined with the path.

## Requirements

|Function|Required header|
|--------------|---------------------|
|**_fullpath**|\<stdlib.h>|
|**_wfullpath**|\<stdlib.h> or \<wchar.h>|

For more compatibility information, see [Compatibility](../../c-runtime-library/compatibility.md).

## Example

```C
// crt_fullpath.c
// This program demonstrates how _fullpath
// creates a full path from a partial path.

#include <stdio.h>
#include <conio.h>
#include <stdlib.h>
#include <direct.h>

void PrintFullPath( char * partialPath )
{
   char full[_MAX_PATH];
   if( _fullpath( full, partialPath, _MAX_PATH ) != NULL )
      printf( "Full path is: %s\n", full );
   else
      printf( "Invalid path\n" );
}

int main( void )
{
   PrintFullPath( "test" );
   PrintFullPath( "\\test" );
   PrintFullPath( "..\\test" );
}
```

```Output
Full path is: C:\Documents and Settings\user\My Documents\test
Full path is: C:\test
Full path is: C:\Documents and Settings\user\test
```

## See also

[File Handling](../../c-runtime-library/file-handling.md)<br/>
[_getcwd, _wgetcwd](getcwd-wgetcwd.md)<br/>
[_getdcwd, _wgetdcwd](getdcwd-wgetdcwd.md)<br/>
[_makepath, _wmakepath](makepath-wmakepath.md)<br/>
[_splitpath, _wsplitpath](splitpath-wsplitpath.md)<br/>