Using the AppImage format you can package desktop applications as AppImages that run on common Linux-based operating systems, such as RHEL, CentOS, Ubuntu, Fedora, Debian and derivatives.
Providing an AppImage for distributing application has, among others, these advantages: Applications packaged as an AppImage can run on many distributions (including Debian, Ubuntu, Fedora, openSUSE, Linux Mint, and others) One app = one file = super simple for users: just download one AppImage file, make it executable, and run No unpacking or installation necessary No root needed No system libraries changed Works out of the box, no installation of runtimes needed Optional desktop integration with appimaged Optional binary delta updates, e.g., for continuous builds (only download the binary diff) using AppImageUpdate Can optionally GPG2-sign your AppImages (inside the file) Works on Live ISOs Can use the same AppImages when dual-booting multiple distributions Can be listed in the AppImageHub central directory of available AppImages Can double as a self-extracting compressed archive with the --appimage-extract parameter
Running an AppImage mounts the filesystem image and transparently runs the contained application. So the usage of an AppImage normally should equal the usage of the application contained in it. However, there is special functionality, as described here. If an AppImage you have received does not support these options, ask the author of the AppImage to recreate it using the latest tooling).
If you invoke an AppImage built with a recent version of AppImageKit with one of these special command line arguments, then the AppImage will behave differently: --appimage-help prints the help options --appimage-offset prints the offset at which the embedded filesystem image starts, and then exits. This is useful in case you would like to loop-mount the filesystem image using the mount -o loop,offset=... command --appimage-extract extracts the contents from the embedded filesystem image, then exits. This is useful if you are using an AppImage on a system on which FUSE is not available --appimage-mount mounts the embedded filesystem image and prints the mount point, then waits until it is killed. This is useful if you would like to inspect the contents of an AppImage without executing the contained payload application --appimage-version prints the version of AppImageKit, then exits. This is useful if you would like to file issues --appimage-updateinformation prints the update information embedded into the AppImage, then exits. This is useful for debugging binary delta updates --appimage-signature prints the digital signature embedded into the AppImage, then exits. This is useful for debugging binary delta updates. If you would like to validate the embedded signature, you should use the validate command line tool that is part of AppImageKit
Normally the application contained inside an AppImage will store its configuration files wherever it normally stores them (most frequently somewhere inside $HOME ). If you invoke an AppImage built with a recent version of AppImageKit and have one of these special directories in place, then the configuration files will be stored alongside the AppImage. This can be useful for portable use cases, e.g., carrying an AppImage on a USB stick, along with its data. If there is a directory with the same name as the AppImage plus .home , then $HOME will automatically be set to it before executing the payload application If there is a directory with the same name as the AppImage plus .config , then $XDG CONFIG HOME will automatically be set to it before executing the payload application
Example: Imagine you want to use the Leafpad text editor, but carry its settings around with the executable. You can do the following:
Note that the file leafpadrc was written in the directory we have created before.
The AppImage runtime is a small piece of code that becomes part of every AppImage. It mounts the AppImage and execu
