CreateDirectoryA function (fileapi.h)

Creates a new directory. If the underlying file system supports security on files and directories, the function applies a specified security descriptor to the new directory.

To specify a template directory, use the CreateDirectoryEx function.

To perform this operation as a transacted operation, use the CreateDirectoryTransacted function.


BOOL CreateDirectoryA(
  [in]           LPCSTR                lpPathName,
  [in, optional] LPSECURITY_ATTRIBUTES lpSecurityAttributes


[in] lpPathName

The path of the directory to be created.

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.


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.

[in, optional] lpSecurityAttributes

A pointer to a SECURITY_ATTRIBUTES structure. The lpSecurityDescriptor member of the structure specifies a security descriptor for the new directory. If lpSecurityAttributes is NULL, the directory gets a default security descriptor. The ACLs in the default security descriptor for a directory are inherited from its parent directory.

The target file system must support security on files and directories for this parameter to have an effect. (This is indicated when GetVolumeInformation returns FS_PERSISTENT_ACLS.)

Return value

If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero. To get extended error information, call GetLastError. Possible errors include the following.

Return code Description
The specified directory already exists.
One or more intermediate directories do not exist; this function will only create the final directory in the path.


Some file systems, such as the NTFS file system, support compression or encryption for individual files and directories. On volumes formatted for such a file system, a new directory inherits the compression and encryption attributes of its parent directory.

An application can obtain a handle to a directory by calling CreateFile with the FILE_FLAG_BACKUP_SEMANTICS flag set. For a code example, see CreateFile.

To support inheritance functions that query the security descriptor of this object may heuristically determine and report that inheritance is in effect. See Automatic Propagation of Inheritable ACEs for more information.

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


For an example, see Retrieving and Changing File Attributes.


The fileapi.h header defines CreateDirectory 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.


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

See also




Creating and Deleting Directories

Directory Management Functions