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STATUS_NO_EAS_ON_FILE
Extended file attributes are file system features that enable users to associate computer files with metadata not interpreted by the filesystem, whereas regular attributes have a purpose strictly defined by the filesystem (such as permissions or records of creation and modification times). Unlike forks, which can usually be as large as the maximum file size, extended attributes are usually limited in size to a value significantly smaller than the maximum file size. Typical uses include storing the author of a document, the character encoding of a plain-text document, or a checksum, cryptographic hash or digital certificate, and discretionary access control information.
In Unix-like systems, extended attributes are usually abbreviated as xattr.
On Windows NT, limited-length extended attributes are supported by FAT, HPFS, and NTFS. This was implemented as part of the OS/2 subsystem. They are notably used by the NFS server of the Interix POSIX subsystem in order to implement Unix-like permissions. The Windows Subsystem for Linux added in the Windows 10 Anniversary Update uses them for similar purposes, storing the Linux file mode, owner, device ID (if applicable), and file times in the extended attributes.
Additionally, NTFS can store arbitrary-length extended attributes in the form of alternate data streams (ADS), a type of resource fork. Plugins for the file manager Total Commander, like NTFS Descriptions and QuickSearch eXtended support filtering the file list by or searching for metadata contained in ADS. NTFS-3G supports mapping ADS to extended attributes in FUSE; it also maps file attributes that way.
About “What is” service
Many of users are faced with the problem of interpreting errors that occur during the work of operating systems. In some cases, the operating system reports that an error has occurred and displays only an integer error code value. Often it is difficult to even roughly understand the cause of the error from the information given out. Our “what is” service contains a database of errors in Windows, Linux, Macos and Solaris operating systems. The database contains tens of thousands of values. In most cases, the online service will be able to help with the definition of the short name of the error and its detailed description.
Categories
Current version of service supports following types of error and status codes:
| NTSTATUS | Many kernel-mode standard driver routines and driver support routines use the NTSTATUS type for return values. Additionally, drivers provide an NTSTATUS-typed value in an IRP’s IO_STATUS_BLOCK structure when completing IRPs. The NTSTATUS type is defined in Ntdef.h, and system-supplied status codes are defined in Ntstatus.h. |
| Win32 error | Win32 error codes MUST be in the range 0x0000 to 0xFFFF, although Win32 error codes can be used both in 16-bit fields (such as within the HRESULT type specified in section in this article) as well as 32-bit fields. Most values also have a default message defined, which can be used to map the value to a human-readable text message; when this is done, the Win32 error code is also known as a message identifier. |
| HRESULT | HRESULT is a data type used in Windows operating systems, and the earlier IBM/Microsoft OS/2 operating system, to represent error conditions, and warning conditions. The original purpose of HRESULTs was to formally lay out ranges of error codes for both public and Microsoft internal use in order to prevent collisions between error codes in different subsystems of the OS/2 operating system. HRESULTs are numerical error codes. Various bits within an HRESULT encode information about the nature of the error code, and where it came from. HRESULT error codes are most commonly encountered in COM programming, where they form the basis for a standardized COM error handling convention. |
| HTTP Status Code | Hypertext Transfer Protocol (HTTP) response status codes. Status codes are issued by a server in response to a client’s request made to the server. It includes codes from IETF Request for Comments (RFCs), other specifications, and some additional codes used in some common applications of the HTTP. The first digit of the status code specifies one of five standard classes of responses. The message phrases shown are typical, but any human-readable alternative may be provided. |
| errno | Integer value, which is returned by system calls and some library functions in the event of an error to indicate what went wrong. errno is defined by the ISO C standard to be a modifiable lvalue of type int, and must not be explicitly declared; errno may be a macro. errno is thread-local; setting it in one thread does not affect its value in any other thread. |
| Kern Return | Apple Kernel return codes. |
| Ipp Status | The IppStatus constant enumerates the status values returned by the Intel IPP functions, indicating whether the operation is error-free. |
Source code
The service is based on the open source library AllStat. Its sources are available on our git server. We will be grateful for your participation in the finalization of the library and ideas for the development of the service. You can also download ErrorLookup utility and libraries from our site.