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

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

text/x-fortran is the MIME type for files containing Fortran source code.
It tells programs and text editors that the file holds plain text with Fortran-specific syntax. This supports proper formatting and syntax highlighting.

Helps compilers correctly process Fortran code.
Guides IDEs and text editors to apply language-specific features.
Supports both the fixed-form and free-form styles of the language.

Files marked with this MIME type include those with formats like F90, F, FOR, F03, FPP, F08, F77, and F95.

For more details on Fortran and MIME types, see Fortran on Wikipedia and MIME types on MDN.

Associated file extensions

.f90, .f, .for, .f03, .fpp, .f08, .f77, .f95

Usage Examples

HTTP Header

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


    Content-Type: text/x-fortran

HTML

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


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

Associated file extensions

.f90, .f, .for, .f03, .fpp, .f08, .f77, .f95

FAQs

How do I configure Apache to serve Fortran files with the correct MIME type?

You can enable the correct MIME type by modifying your .htaccess file or the main server configuration. Add the line AddType text/x-fortran .f .f90 .f95 .for to ensure Apache sends the correct headers for these files.

Can web browsers execute text/x-fortran files?

No, web browsers cannot execute Fortran code. Since text/x-fortran represents source code, browsers will usually display the file contents as plain text or prompt the user to download the file. To run the code, it must be compiled using a compiler like gfortran or ifort.

What common file extensions are associated with text/x-fortran?

This MIME type covers a wide range of Fortran standards. Common extensions include the older fixed-form style like f and f77, as well as modern free-form extensions like f90, f95, and f03.

How do I set up Nginx to recognize Fortran source code?

In Nginx, you should add the file extensions to the types block within your mime.types file or nginx.conf. Use the syntax: text/x-fortran f f90 f95 f03; to ensure the server identifies these files correctly.

Why does the MIME type start with "x-"?

The x- prefix indicates that text/x-fortran is a non-standard or experimental type not officially registered with IANA. However, it is the de facto standard used by most operating systems and web servers to identify Fortran source code.

Why is the text/x-fortran MIME type important for text editors?

Correct MIME identification allows text editors and IDEs to apply specific syntax highlighting and linting. This is crucial for Fortran because the syntax rules change significantly between versions (e.g., the column-dependent format of f77 versus the free-form format of f90).

Is there a security risk in serving text/x-fortran files?

Serving these files exposes your source code to the public. While the files themselves are harmless text, they may reveal proprietary algorithms or logic. If the code is not meant to be public, ensure your server is configured to deny access to these extensions.

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.