Desktop entries - ArchWiki

# Desktop entries

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The XDG Desktop Entry specification defines a standard for applications to integrate into application menus of desktop environments implementing the XDG Desktop Menu specification.

## Basics

Each desktop entry must have a `Type` and a `Name` key and can optionally define its appearance in the application menu.

The three available types are:

Application
  Defines how to launch an application and what MIME types it supports (used by XDG MIME Applications). With XDG Autostart Application entries can be started automatically by placing them in specific directories. Application entries use the `.desktop` file extension. See #Application entry.

Link
  Defines a shortcut to a `URL`. Link entries use the `.desktop` file extension.

Directory
  Defines the appearance of a submenu in the application menu. Directory entries use the `.directory` file extension.

The following sections will roughly explain how these are created and validated.

## Application entry

Desktop entries for applications, or `.desktop` files, are generally a combination of meta information resources and a shortcut of an application. These files usually reside in `/usr/share/applications/` or `/usr/local/share/applications/` for applications installed system-wide, or `~/.local/share/applications/` for user-specific applications. User entries take precedence over system entries.

### File example

Following is an example of its structure with additional comments. The example is only meant to give a quick impression, and does not show how to utilize all possible entry keys. The complete list of keys can be found in the freedesktop specification.

    [Desktop Entry]

    # The type as listed above
    Type=Application

    # The version of the desktop entry specification to which this file complies
    Version=1.0

    # The name of the application
    Name=jMemorize

    # A comment which can/will be used as a tooltip
    Comment=Flash card based learning tool

    # The path to the folder in which the executable is run
    Path=/opt/jmemorise

    # The executable of the application, possibly with arguments.
    Exec=jmemorize

    # The name of the icon that will be used to display this entry
    Icon=jmemorize

    # Describes whether this application needs to be run in a terminal or not
    Terminal=false

    # Describes the categories in which this entry should be shown
    Categories=Education;Languages;Java;

Note: Only `Type` and `Name` are required.

### Key definition

All recognized entries can be found on the freedesktop site. For example, the `Type` key defines three types of desktop entries: Application (type 1), Link (type 2) and Directory (type 3).

- `Version` key does not stand for the version of the application, but for the version of the desktop entry specification to which this file complies.

- `Name`, `GenericName` and `Comment` often contain redundant values in the form of combinations of them, like:

    Name=Pidgin Internet Messenger
    GenericName=Internet Messenger

or

    Name=NoteCase notes manager
    Comment=Notes Manager

This should be avoided, as it will only be confusing to users. The `Name` key should only contain the name, or maybe an abbreviation/acronym if available.

- `GenericName` should state what you would generally call an application that does what this specific application offers (i.e. Firefox is a "Web Browser").
- `Comment` is intended to contain any useful additional information.

### Validation

As some keys have become deprecated over time, you may want to validate your desktop entries using desktop-file-validate(1) which is part of the desktop-file-utils package. To validate, run:

    $ desktop-file-validate <your desktop file>

This will give you very verbose and useful warnings and error messages.

### Installation

Use desktop-file-install(1) to install desktop file into target directory. For example:

    $ desktop-file-install --dir=~/.local/share/applications ~/app.desktop

### Update database of desktop entries

To make desktop entries defined in `~/.local/share/applications` work, run the following command:

    $ update-desktop-database ~/.local/share/applications

## Icons

See also the Icon Theme Specification.

### Common image formats

Here is a short overview of image formats commonly used for icons.

Support for image formats for icons as specified by the freedesktop.org standard.
Extension | Full Name and/or Description | Graphics Type | Container Format | Supported
--- | --- | --- | --- | ---
.png | Portable Network Graphics | Raster | No | Yes
.svg(z) | Scalable Vector Graphics | Vector | No | Yes (optional)
.xpm | X PixMap | Raster | No | Yes (deprecated)
.gif | Graphics Interchange Format | Raster | No | No
.ico | MS Windows Icon Format | Raster | Yes | No
.icns | Apple Icon Image | Raster | Yes | No

### Converting icons

This article or section is a candidate for merging with ImageMagick#Usage.

Notes: Belongs there. (Discuss in Talk:Desktop entries#)

If you stumble across an icon which is in a format that is not supported by the freedesktop.org standard (like `gif` or `ico`), you can use the convert tool (which is part of the imagemagick package) to convert it to a supported/recommended format, e.g.:

    $ convert <icon name>.gif <icon name>.png

If you convert from a container format like `ico`, you will get all images that were encapsulated in the `ico` file in the form `<icon name>-<number>.png`. If you want to know the size of the image, or the number of images in a container file like `ico` you can use the identify tool (also part of the imagemagick package):

    $ identify /usr/share/vlc/vlc48x48.ico

    /usr/share/vlc/vlc48x48.ico[0] ICO 32x32 32x32+0+0 8-bit DirectClass 84.3kb
    /usr/share/vlc/vlc48x48.ico[1] ICO 16x16 16x16+0+0 8-bit DirectClass 84.3kb
    /usr/share/vlc/vlc48x48.ico[2] ICO 128x128 128x128+0+0 8-bit DirectClass 84.3kb
    /usr/share/vlc/vlc48x48.ico[3] ICO 48x48 48x48+0+0 8-bit DirectClass 84.3kb
    /usr/share/vlc/vlc48x48.ico[4] ICO 32x32 32x32+0+0 8-bit DirectClass 84.3kb
    /usr/share/vlc/vlc48x48.ico[5] ICO 16x16 16x16+0+0 8-bit DirectClass 84.3kb

As you can see, the example ico file, although its name might suggest a single image of size 48x48, contains no less than 6 different sizes, of which one is even greater than 48x48, namely 128x128.

Alternatively, you can use icotool (from icoutils) to extract png images from ico container:

    $ icotool -x <icon name>.ico

For extracting images from .icns container, you can use icns2png (provided by libicns):

    $ icns2png -x <icon name>.icns

### Obtaining icons

Although packages that already ship with a .desktop file most certainly contain an icon or a set of icons, there is sometimes the case when a developer has not created a .desktop file, but may ship icons, nonetheless. So a good start is to look for icons in the source package. You can i.e. first filter for the extension with find and then use grep to filter further for certain buzzwords like the package name, "icon", "logo", etc, if there are quite a lot of images in the source package.

    $ find /path/to/source/package -regex ".*\.\(svg\|png\|xpm\|gif\|ico\)$"

If the developers of an application do not include icons in their source packages, the next step would be to search on their web sites. Some projects, like i.e. tvbrowser have an artwork/logo page where additional icons may be found. If a project is multi-platform, there may be the case that even if the linux/unix package does not come with an icon, the Windows package might provide one. If the project uses a Version control system like CVS/SVN/etc. and you have some experience with it, you also might consider browsing it for icons. If everything fails, the project might simply have no icon/logo yet.

### Icon path

The freedesktop.org standard specifies in which order and directories programs should look for icons:

1. `$HOME/.icons` (for backwards compatibility)
2. `$XDG_DATA_DIRS/icons`
3. `/usr/share/pixmaps`

## Tools

### gendesk

gendesk started as an Arch Linux-specific tool for generating .desktop files by fetching the needed information directly from PKGBUILD files. Now it is a general tool that takes command-line arguments.

Icons can be automatically downloaded from openiconlibrary, if available. (The source for icons is configurable).

#### How to use

- Add `gendesk` to makedepends

- Start the `prepare()` function with:

    gendesk --pkgname "$pkgname" --pkgdesc "$pkgdesc"

- Alternatively, if an icon is already provided ($pkgname.png, for instance). The `-n` flag is for not downloading an icon or using the default icon. Example:

    gendesk -n --pkgname "$pkgname" --pkgdesc "$pkgdesc"

- `$srcdir/$pkgname.desktop` will be created and can be installed in the `package()` function with:

    install -Dm644 "$pkgname.desktop" "$pkgdir/usr/share/applications/$pkgname.desktop"

- The icon can be installed with:

    install -Dm644 "$pkgname.png" "$pkgdir/usr/share/pixmaps/$pkgname.png"

- Use `--name='Program Name'` for choosing a name for the menu entry.

- Use `--exec='/opt/some_app/elf --some-arg --other-arg'` for setting the exec field.

- See the gendesk project for more information.

### lsdesktopf

lsdesktopfAUR can list available .desktop files or search their contents.

    $ lsdesktopf
    $ lsdesktopf --list
    $ lsdesktopf --list gtk zh_TW,zh_CN,en_GB

It can also perform MIME-type-related searches. See XDG MIME Applications#lsdesktopf.

### fbrokendesktop

The fbrokendesktopAUR Bash script detects broken `Exec` values pointing to non-existent paths. Without any arguments it uses preset directories in the `DskPath` array. It shows only broken .desktop with full path and filename that is missing.

Examples

    $ fbrokendesktop
    $ fbrokendesktop /usr
    $ fbrokendesktop /usr/share/apps/kdm/sessions/icewm.desktop

## Tips and tricks

### Run a desktop file from a terminal

Install the dex package and run `dex /path/to/application.desktop`.

### Hide desktop entries

Firstly, copy the desktop entry file in question to `~/.local/share/applications` to avoid your changes being overwritten.

Then, to hide the entry in all environments, open the desktop entry file in a text editor and add the following line: `NoDisplay=true`.

To hide the entry in a specific desktop, add the following line to the desktop entry file: `NotShowIn=desktop-name`

where desktop-name can be option such as GNOME, Xfce, KDE etc. A desktop entry can be hidden in more than desktop at once - simply separate the desktop names with a semi-colon.

### Modify environment variables

To set environment variables, copy the .desktop file from `/usr/share/applications/` to `$XDG_DATA_HOME/` (`~/.local/share/applications/`) and edit the `Exec=` command line by prepending env. For example:

    ~/.local/share/applications/abiword.desktop

    Exec=env LANG=he_IL.UTF-8 abiword %U

## See also

- Wikipedia:.desktop
- Information for developers

Categories:

- Freedesktop.org
- Configuration files
- Package development

Hidden category:

- Pages or sections flagged with Template:Merge