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File Attribute Constants

File attributes are metadata values stored by the file system on disk and are used by the system and are available to developers via various file I/O APIs. For a list of related APIs and topics, see the See also section.

Example

FILE_BASIC_INFO basicInfo;
    BOOL result;

    result = GetFileInformationByHandleEx( hFile,
                                               FileBasicInfo,
                                               &basicInfo,
                                               sizeof(basicInfo));

\\...

printf("  File Attributes: ");
    PrintFileAttributes(basicInfo.FileAttributes);

\\...
VOID
PrintFileAttributes(
    ULONG FileAttributes
    )
{
    
    if (FileAttributes & FILE_ATTRIBUTE_ARCHIVE) {
        printf("Archive ");
    }
    if (FileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
        printf("Directory ");
    }
    if (FileAttributes & FILE_ATTRIBUTE_READONLY) {
        printf("Read-Only ");
    }
}

Example taken from a Windows Classic Sample on GitHub.

Constant/value Description
FILE_ATTRIBUTE_READONLY
1 (0x00000001)
A file that is read-only. Applications can read the file, but cannot write to it or delete it. This attribute is not honored on directories. For more information, see You cannot view or change the Read-only or the System attributes of folders in Windows Server 2003, in Windows XP, in Windows Vista or in Windows 7.
FILE_ATTRIBUTE_HIDDEN
2 (0x00000002)
The file or directory is hidden. It is not included in an ordinary directory listing.
FILE_ATTRIBUTE_SYSTEM
4 (0x00000004)
A file or directory that the operating system uses a part of, or uses exclusively.
FILE_ATTRIBUTE_DIRECTORY
16 (0x00000010)
The handle that identifies a directory.
FILE_ATTRIBUTE_ARCHIVE
32 (0x00000020)
A file or directory that is an archive file or directory. Applications typically use this attribute to mark files for backup or removal.
FILE_ATTRIBUTE_DEVICE
64 (0x00000040)
This value is reserved for system use.
FILE_ATTRIBUTE_NORMAL
128 (0x00000080)
A file that does not have other attributes set. This attribute is valid only when used alone.
FILE_ATTRIBUTE_TEMPORARY
256 (0x00000100)
A file that is being used for temporary storage. File systems avoid writing data back to mass storage if sufficient cache memory is available, because typically, an application deletes a temporary file after the handle is closed. In that scenario, the system can entirely avoid writing the data. Otherwise, the data is written after the handle is closed.
FILE_ATTRIBUTE_SPARSE_FILE
512 (0x00000200)
A file that is a sparse file.
FILE_ATTRIBUTE_REPARSE_POINT
1024 (0x00000400)
A file or directory that has an associated reparse point, or a file that is a symbolic link.
FILE_ATTRIBUTE_COMPRESSED
2048 (0x00000800)
A file or directory that is compressed. For a file, all of the data in the file is compressed. For a directory, compression is the default for newly created files and subdirectories.
FILE_ATTRIBUTE_OFFLINE
4096 (0x00001000)
The data of a file is not available immediately. This attribute indicates that the file data is physically moved to offline storage. This attribute is used by Remote Storage, which is the hierarchical storage management software. Applications should not arbitrarily change this attribute.
FILE_ATTRIBUTE_NOT_CONTENT_INDEXED
8192 (0x00002000)
The file or directory is not to be indexed by the content indexing service.
FILE_ATTRIBUTE_ENCRYPTED
16384 (0x00004000)
A file or directory that is encrypted. For a file, all data streams in the file are encrypted. For a directory, encryption is the default for newly created files and subdirectories.
FILE_ATTRIBUTE_INTEGRITY_STREAM
32768 (0x00008000)
The directory or user data stream is configured with integrity (only supported on ReFS volumes). It is not included in an ordinary directory listing. The integrity setting persists with the file if it's renamed. If a file is copied the destination file will have integrity set if either the source file or destination directory have integrity set.
Windows Server 2008 R2, Windows 7, Windows Server 2008, Windows Vista, Windows Server 2003 and Windows XP: This flag is not supported until Windows Server 2012.
FILE_ATTRIBUTE_VIRTUAL
65536 (0x00010000)
This value is reserved for system use.
FILE_ATTRIBUTE_NO_SCRUB_DATA
131072 (0x00020000)
The user data stream not to be read by the background data integrity scanner (AKA scrubber). When set on a directory it only provides inheritance. This flag is only supported on Storage Spaces and ReFS volumes. It is not included in an ordinary directory listing.
Windows Server 2008 R2, Windows 7, Windows Server 2008, Windows Vista, Windows Server 2003 and Windows XP: This flag is not supported until Windows 8 and Windows Server 2012.
FILE_ATTRIBUTE_EA
262144 (0x00040000)
A file or directory with extended attributes.

IMPORTANT: This constant is for internal use only.
FILE_ATTRIBUTE_PINNED
524288 (0x00080000)
This attribute indicates user intent that the file or directory should be kept fully present locally even when not being actively accessed. This attribute is for use with hierarchical storage management software.
FILE_ATTRIBUTE_UNPINNED
1048576 (0x00100000)
This attribute indicates that the file or directory should not be kept fully present locally except when being actively accessed. This attribute is for use with hierarchical storage management software.
FILE_ATTRIBUTE_RECALL_ON_OPEN
262144 (0x00040000)
This attribute only appears in directory enumeration classes (FILE_DIRECTORY_INFORMATION, FILE_BOTH_DIR_INFORMATION, etc.). When this attribute is set, it means that the file or directory has no physical representation on the local system; the item is virtual. Opening the item will be more expensive than normal, e.g. it will cause at least some of it to be fetched from a remote store.
FILE_ATTRIBUTE_RECALL_ON_DATA_ACCESS
4194304 (0x00400000)
When this attribute is set, it means that the file or directory is not fully present locally. For a file that means that not all of its data is on local storage (e.g. it may be sparse with some data still in remote storage). For a directory it means that some of the directory contents are being virtualized from another location. Reading the file / enumerating the directory will be more expensive than normal, e.g. it will cause at least some of the file/directory content to be fetched from a remote store. Only kernel-mode callers can set this bit.

File system mini filters below the 180000 – 189999 altitude range (FSFilter HSM Load Order Group) must not issue targeted cached reads or writes to files that have this attribute set. This could lead to cache pollution and potential file corruption. For more information, see Handling placeholders.

Requirements

Requirement Value
Minimum supported client Windows XP [desktop apps only]
Minimum supported server Windows Server 2003 [desktop apps only]
Header WinNT.h (include Windows.h)

See also

Compression Attribute

Creating and Opening Files

CreateFile

CreateFileTransacted

GetFileAttributes

GetFileAttributesEx

GetFileAttributesTransacted

GetFileInformationByHandle

GetFileInformationByHandleEx

SetFileAttributes

SetFileAttributesTransacted

SetFileInformationByHandle