Yes, FreeDesktop are cool but out of the box many don't come with a proper set of URI handlers. How to open, for example vnc:// or ssh:// or icr:// - or some that you may make up in the future. Some Web-Browsers, such as Firefox, have a built-in configuration that you can set per Browser profile, but that won't affect the whole desktop or other browsers, or other system users!
This How-To will demonstrate how to create a custom URI handler, for all desktop applications using FreeDesktop standard methods. We'll simply update the list of mime-handlers and create the custom wrapper. To start the configuration will work for the current user, but can be upgraded to a system-wide configuration.
Registering Custom URI Handler
There is a file,
~/.local/share/applications/mimeapps.list that contains a list of MIME handlers.
Take note of the special MIME category of "x-scheme-handler", with it's sub-type begin a URI scheme.
Here is a sample:
To create a custom handler, simply create an entry under the [Added Associations] section. We have two examples listed, one for vnc and the other for SSH. The format is x-scheme-handler/%s=%d, where %s is the scheme name and %d is the desktop entry file.
Creating the Handlers
Some handlers are simple enough you can just pass the parameters directly, others may need some wrapper script.
These handlers are created in the users application directory:
Here is a sample vnc:// handler Desktop file
[Desktop Entry] Version=1.0 Type=Application Exec=/home/atom/vnc-handler.sh %u Icon=vncviewer StartupNotify=true Terminal=false Categories=Utility;X-XFCE;X-Xfce-Toplevel; MimeType=x-scheme-handler/vnc Name=VNC Launcher Comment=Launch VNC
And VNC Handler had to be specially built, it's not built-in, that's vnc-handler.sh
#!/bin/bash host=$(echo "$1"|perl -ne '/vnc:\/\/(.+)[:\/]/ && print $1') port=$(echo "$1"|perl -ne '/:(\d+)$/ && print $1') vncviewer $host::$port
That will properly respond to URIs like: vnc://host:5900.
And here is a another example for ssh:// handler Desktop file (in
[Desktop Entry] Version=1.0 Type=Application Exec=/home/atom/xdg/ssh-handler.sh %u Icon=roxterm StartupNotify=true Terminal=false Categories=Utility;X-XFCE;X-Xfce-Toplevel; MimeType=x-scheme-handler/ssh Name=SSH Launcher Comment=Launch SSH
Another special handler that's exo-ssh-handler.sh
#!/bin/bash ( set -o xtrace echo "" echo "$1" | perl -ne '/^(ssh):\/\/([^:@]*)?:?([^:@]*)?[:@]?([^:@\/\?\#]*)/ && print "$1\n"; print "$2\n"; print "$3\n"; print "$4\n"' echo "" # 1 2 3 4 5 6 7 8 9 user=$(echo "$1"|perl -ne '/ssh:\/\/([^:@]*)(:?.*)@?(\w+)/ && print $1') [ -z "$user" ] && user=$USER host=$(echo "$1"|perl -ne '/ssh:\/\/.*([\w\.]*):/ && print $1') port=$(echo "$1"|perl -ne '/:(\d+)$/ && print $1') [ -z "$port" ] && port="22" roxterm --separate --title="SSH $1" --execute ssh -p $port $user@$host ) >> /tmp/exo.log 2>&1
That will properly respond to URIs like: ssh://host or ssh://host:2200
The gvfs system may take precident over what you have specified here, specifically the ssh:// handler is aliased to sftp://.
Looking in the directory: /usr/share/gvfs/mounts/ we can find the handlers.
sftp.desktop and remove the SchemeAlias, like the following example.
[Mount] Type=sftp Exec=/usr/libexec/gvfsd-sftp AutoMount=false Scheme=sftp # SchemeAliases=ssh DefaultPort=22 HostnameIsInetAddress=true
Shout out to "TGEN" on #xfce for some tips/tricks.