The Guide to getting LilyPond Point and Click going with Atom under Fedora 33

[Andrew Bernard]

The Guide to getting LilyPond Point and Click going with Atom under 
Fedora 33
--------------------------------------------------------------------------------------------------------------

The NR leaves out some important information about how to configure a Ubuntu
system to use Gvim for point and click from Lilypond PDF files. Where 
the NR is
substantially correct, that information is copied here.


Requirements
------------

Fedora 33
Document Viewer (evince)
Atom 1.52.0
[assumes bash shell]


Setting the EDITOR variable
---------------------------

Lilypond uses the environment variable EDITOR to select which editor to 
use to
display point and click links. For Atom, simply use the value 'atom':

export EDITOR=gvim

Setting LYEDITOR is not required.

You can start evince from a terminal command to view a PDF. But if you 
want to
click on a PDF in GNOME Nautilus to view it then just exporting this 
variable
from the various bash startup files is inadequate. Gnome is started by 
Xsession
in X11 before terminals and shells. Therefore it is unable to see 
environment
variables set in .bashrc (or .bash_profile, etc). To resolve this matter,
recall that Xsession uses the startup file $HOME/.xsessionrc. For 
environment
variables that are to be shared between GNOME applications and terminal 
shells,
do the following. Create a file for variable declarations, of arbitrary 
name.
Add the EDITOR setting to that file:

 $ echo 'export EDITOR=atom' > ~/.my_env_vars

Then edit ~/.xsessionrc to contain:

if [ -f ~/.my_env_vars ]; then
    . ~/.my_env_vars
fi

Now also add these same lines to ~/.bashrc. Some like to use 
.bash_profile or
other mechanisms, but the principle is the same. Manage any shared variables
that Nautilus and a bash shell both need in this third file. To make 
this take
effect, logout and login again so that a new Xsession is started.


Installing Atom
---------------
Atom is not in the standard repository for Fedora.

# dnf install $(curl -sL 
"https://api.github.com/repos/atom/atom/releases/latest"; | grep 
"https.*atom.x86_64.rpm" | cut -d '"' -f 4)



Configuring the GNOME 3 Desktop
-------------------------------

Create the file 'lilypond-invoke-editor.desktop':

[Desktop Entry]
Version=1.0
Name=lilypond-invoke-editor
GenericName=Textedit URI handler
Comment=URI handler for textedit:
Exec=lilypond-invoke-editor %u
Terminal=false
Type=Application
MimeType=x-scheme-handler/textedit;
Categories=Editor
NoDisplay=true

Run:

$ xdg-desktop-menu install ./lilypond-invoke-editor.desktop
$ xdg-mime default lilypond-invoke-editor.desktop x-scheme-handler/textedit

Check that this works using xdg-open.

$ xdg-open textedit:///etc/issue:1:0:0

If all is correct lilypond-invoke-editor will run and display the file 
in Atom, with the cursor
at the right point.