What is MIME type "text/x-c"?

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

The MIME type text/x-c signals that the file is plain text formatted as C code. It is used to mark files written in the C programming language and sometimes for DTS (Device Tree Source) code.

It helps software tools, editors, and browsers to apply the correct syntax highlighting and formatting rules. The x- prefix indicates that this MIME type is non-standard or experimental, which is common with developer-specific content.

Primary Use: It identifies C source code for proper editing and code inspection.
Secondary Use: It marks DTS files, which define hardware layouts in embedded systems.
Functionality: It allows code editors and browsers to activate programming-aware features, like syntax highlighting and code folding.

For more details on MIME standards, visit IANA Media Types.

Associated file extensions

.dts, .c

Usage Examples

HTTP Header

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


    Content-Type: text/x-c

HTML

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


    <a href="file.dat" type="text/x-c">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', 'text/x-c');    
      res.end('Content here');    
    }).listen(3000);

Associated file extensions

.dts, .c

FAQs

What is the text/x-c MIME type used for?

This MIME type is primarily used to identify source code written in the C programming language. It tells web servers and browsers that the file, typically ending in .c, contains code rather than generic text, often enabling syntax highlighting in developer tools.

How do I configure Apache to serve .c files correctly?

To associate C source files with this MIME type in Apache, add the following line to your .htaccess file or main configuration: AddType text/x-c .c .dts. This ensures browsers handle the files as code.

Why does this MIME type start with an x- prefix?

The x- prefix signifies that text/x-c is a non-standard or private subtype not strictly defined by IANA standards. Despite this, it is widely recognized and supported by virtually all web servers and operating systems for identifying C code.

How do I enable text/x-c support in Nginx?

In your Nginx configuration (usually inside mime.types or a types block), add the mapping: text/x-c c dts;. This instructs the server to send the text/x-c header for both C source files and Device Tree Source files.

Will a web browser execute the code in a text/x-c file?

No, web browsers do not compile or run C code. When a browser encounters this MIME type, it will simply display the contents as plain text, allowing you to read the source code but not execute the program.

Why are .dts files associated with text/x-c?

Device Tree Source (.dts) files describe hardware structures for embedded systems and use a syntax very similar to C. Consequently, they are often labeled as text/x-c so that text editors apply the correct syntax highlighting and formatting.

Is it safe to open files with the text/x-c MIME type?

Yes, these files are plain text and cannot execute malicious code simply by being opened in a text editor or browser. However, as with any source code, you should never compile and run code from untrusted sources.

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.