Ubuntu – .desktop file running sh script “There was an error launching the application.”

Modern Answer

gtk-launch <app-name> - where <app-name> is the file name of the .desktop file, with or without the .desktop extension.

See another answer on this thread for more details. I got this info from that answer.

Deprecated shell tools answer

Written a long time ago - see the comments below this answer as to why this approach won't work for many desktop files.

The command that is run is contained inside the desktop file, preceded by Exec= so you could extract and run that by:

$(grep '^Exec' filename.desktop | tail -1 | sed 's/^Exec=//' | sed 's/%.//' \
| sed 's/^"//g' | sed 's/" *$//g') &

To break that down

grep  '^Exec' filename.desktop    # - finds the line which starts with Exec
| tail -1                         # - only use the last line, in case there are 
                                  #   multiple
| sed 's/^Exec=//'                # - removes the Exec from the start of the line
| sed 's/%.//'                    # - removes any arguments - %u, %f etc
| sed 's/^"//g' | sed 's/" *$//g' # - removes " around command (if present)
$(...)                            # - means run the result of the command run 
                                  #   here
&                                 # - at the end means run it in the background

You could put this in a file, say ~/bin/deskopen with the contents

#!/bin/sh
$(grep '^Exec' $1 | tail -1 | sed 's/^Exec=//' | sed 's/%.//' \
| sed 's/^"//g' | sed 's/" *$//g') &

Then make it executable

chmod +x ~/bin/deskopen

And then you could do, e.g.

deskopen /usr/share/applications/ubuntu-about.desktop

The arguments (%u, %F etc) are detailed here. None of them are relevant for launching at the command line.

Try following text in your .desktop file.

[Desktop Entry]
Version=1.0
Name=ProgramName
Comment=This is my comment
Exec=/usr/share/MyApp/MyApp.py
Icon=/usr/share/MyApp/MyApp.py
Path=/usr/share/MyApp/
Terminal=false
Type=Application
Categories=Utility;Application;