mimeopen.

mimeopen [OPTIONS] FILE...

--help
    Displays usage information and exits.

--version
    Shows the command's version and exits.

FILE...
    One or more file paths to be opened. The command determines the MIME type for each file and opens it with the appropriate application.

The mimeopen command, while not a universally standard Linux utility across all distributions (often its functionality is encapsulated within tools like xdg-open), serves the purpose of opening a specified file using the default application associated with its detected MIME type. It streamlines the process of launching various document types, images, or multimedia files by abstracting away the need to know which specific application handles them.

When invoked, mimeopen typically first determines the MIME type of the given file (e.g., text/plain, image/jpeg, application/pdf). It then consults a database of file associations, usually managed by the desktop environment (like XFCE, GNOME, KDE, or LXQt), to find the preferred application for that MIME type. Finally, it attempts to launch the detected application with the file as an argument. This command simplifies user interaction, allowing them to simply "open" a file without manually selecting an application.

The mimeopen command is not a standard, pre-installed utility on all Linux distributions. Its functionality is most commonly provided by the xdg-open command (part of xdg-utils), which serves as a cross-desktop utility for opening files and URLs. If mimeopen is present, it might be a specific desktop environment's internal helper script, a third-party utility, or a simplified wrapper that performs a subset of xdg-open's capabilities. Users should typically prefer xdg-open for robust and cross-environment file opening.

mimeopen (or its equivalent) relies on underlying utilities like file(1) or desktop environment-specific libraries to accurately determine the MIME type of a given file.

The choice of which application opens a specific MIME type is typically configured through the desktop environment's settings or by using utilities like xdg-mime to set preferred applications.

The concept of opening files based on their MIME type emerged with the rise of graphical desktop environments on Linux and Unix-like systems. Early attempts involved simple scripts and configuration files (like mailcap). Over time, more sophisticated frameworks like xdg-utils (which xdg-open is a part of) were developed by freedesktop.org to standardize this behavior across different desktop environments (GNOME, KDE, XFCE, LXQt, etc.). While mimeopen itself isn't a historically distinct project, it represents the core mechanism that xdg-open and similar tools employ to provide a consistent "open file" experience.

xdg-open(1), file(1), xdg-mime(1), xdg-settings(1)