What is MIME type "application/x-starwriter"?

A MIME type is a string that tells browsers and other tools how to handle a particular kind of file.

application/x-starwriter is a MIME type that signals a StarWriter document produced by the StarOffice suite. It tells your computer which application should open the file and how to process its content.

Files with this type use a specific, vendor-defined format. This setup allows the system to recognize that the file is a rich text document with formatting, images, and other embedded elements. It is a non-standard ("x-") MIME type reserved for special cases.

The document commonly has the file extension SDW.

Document creation: Stores full-featured word processing content.
Legacy support: Common in older office suites like StarOffice.
File recognition: Helps operating systems and browsers know which application to use.

This MIME type is essential for proper handling and compatibility in environments that work with legacy document formats. For more information on MIME types, check out the Media Type article.

Associated file extensions

.sdw

Usage Examples

HTTP Header

When serving content with this MIME type, set the Content-Type header:


    Content-Type: application/x-starwriter

HTML

In HTML, you can specify the MIME type in various elements:


    <a href="file.dat" type="application/x-starwriter">Download file</a>

Server-side (Node.js)

Setting the Content-Type header in Node.js:


    const http = require('http');    
    
    http.createServer((req, res) => {    
      res.setHeader('Content-Type', 'application/x-starwriter');    
      res.end('Content here');    
    }).listen(3000);

Associated file extensions

.sdw

FAQs

Which software opens application/x-starwriter files?

Files with the MIME type application/x-starwriter are legacy documents originally created by StarOffice. You can currently open them using Apache OpenOffice or LibreOffice, which maintain backward compatibility for the .sdw extension.

How do I configure Apache to serve StarWriter files?

To ensure your Apache web server handles these files correctly, add the specific directive to your .htaccess or configuration file. Use the line: AddType application/x-starwriter .sdw.

Can web browsers display application/x-starwriter content directly?

No, modern web browsers like Chrome, Firefox, and Edge do not have native support for rendering StarWriter documents. Instead of displaying the content, the browser will prompt the user to download the file to their computer.

What does the 'x-' prefix mean in this MIME type?

The x- prefix indicates that application/x-starwriter is a non-standard or vendor-specific type, not originally registered with IANA. While common in the past for StarOffice, modern applications usually prefer standard formats like application/vnd.oasis.opendocument.text (ODT).

How do I add support for this MIME type in Nginx?

For Nginx servers, you need to update your mime.types file to map the extension to the MIME type. Add the entry application/x-starwriter sdw; inside the types { ... } block to ensure correct delivery.

Why is the file downloading as application/octet-stream?

If a server is not configured to recognize the .sdw extension, it defaults to the generic binary type application/octet-stream. This tells the browser to download the file but fails to inform the operating system which specific application is needed to open it.

Are there security risks associated with this file type?

Yes, as with many legacy office document formats, application/x-starwriter files can potentially contain macros. It is best practice to scan these files for malware and only open them from trusted sources, especially when using older software versions.

What is the modern alternative to application/x-starwriter?

The modern standard that replaced StarWriter formats is the OpenDocument Format. It is recommended to convert these legacy files to .odt (OpenDocument Text), which uses the MIME type application/vnd.oasis.opendocument.text.

General FAQ

What is a MIME type?

A MIME (Multipurpose Internet Mail Extensions) type is a standard that indicates the nature and format of a document, file, or assortment of bytes. MIME types are defined and standardized in IETF's RFC 6838.

MIME types are important because they help browsers and servers understand how to process a file. When a browser receives a file from a server, it uses the MIME type to determine how to display or handle the content, whether it's an image to display, a PDF to open in a viewer, or a video to play.

MIME types consist of a type and a subtype, separated by a slash (e.g., text/html, image/jpeg, application/pdf). Some MIME types also include optional parameters.

How do I find the MIME type for a file?

You can check the file extension or use a file identification tool such as file --mime-type on the command line. Many programming languages also provide libraries to detect MIME types.

Why are multiple MIME types listed for one extension?

Different applications and historical conventions may use alternative MIME identifiers for the same kind of file. Showing them all helps ensure compatibility across systems.