How to get under Linux Mint LMDE5, the path of a launcher through bash commands stored in the launcher?

Question

Linux Mint LMDE5 is a Debian derivative. On the desktop you can create launchers p.e. via GUI, with which you can not only link something, but also store smaller bash code in it. After creating, the launcher can moved to other folder.

Location of the follow .sh file and launcher:

/home/user_name/desktop/a/b/c

With the following code you can print the path to a bash file when you execute it.

Content of the .sh file:

#!/bin/bash
script_path=$(dirname "$(readlink -f "$0")")"/"
echo "$script_path"
sleep 100

Output of the .sh file:

/home/user_name/desktop/a/b/c

The not working launcher "solution":

Content of the launcher file:

bash -c 'launcher_path=$(dirname "$(readlink -f "$0")")"/"; echo "$launcher_path"; sleep 100'

Output of launcher by terminal:

/home/user_name/ # but that should be: /home/user_name/desktop/a/b/c

What does "launcher" mean:

This is a .desktop file, which is common on Linux Mint and LMDE. The file has similarities in structure and tasks to a ".lnk" file under Windows.

Two How too`s for creating "launcher" by Linux Mint GUI:

• https://community.linuxmint.com/tutorial/view/2074
• https://www.youtube.com/watch?v=0CFNCkMKp44

Sample content of a "launcher" (.desktop file):

[Desktop Entry]
Name=test
Exec=bash -c 'xed /home/user/desktop/sample_file.txt'
Comment=
Terminal=true
Icon=cinnamon-panel-launcher
Type=Application
Name[de_DE]=Sample for a launcher file, which open a textfile, which is located on desktop.

Concretization:

Only a suitable modification of the following command line of the launcher is searched:

bash -c 'launcher_path=$(dirname "$(readlink -f "$0")")"/"; echo "$launcher_path"; sleep 100'

It is not looking for any additional scripts or modifications of the operating system.

Answer 1

If you want to know the directory that contains the running script you shouldn't use bash -c, instead you can symlink your script to a user owned directory that contains executable files (commonly ~/.local/bin and ~/bin), and use it the Exec key of your .desktop file. Since you're using Bash you can also replace $0 with the better alternative ${BASH_SOURCE[0]}. (see this answer)

$ pwd
/home/user_name/desktop/a/b/c
$ cat mylauncher.sh
#!/bin/bash
script_path=$(dirname "$(readlink -f "${BASH_SOURCE[0]}")")/
echo "$script_path"
$ ./mylauncher.sh
/home/user_name/desktop/a/b/c/

Adding the symbolic link to ~/bin:

$ pwd
/home/user_name/desktop/a/b/c
$ mkdir -p ~/bin
$ PATH=$HOME/bin:$PATH
$ ln -rs ./mylauncher.sh ~/bin
$ cd
$ pwd
/home/user_name
$ mylauncher.sh
/home/user_name/desktop/a/b/c/

Now you can use Exec=mylauncher.sh in your .desktop file. Some systems already include a check for ~/bin and ~/.local/bin in the .profile file. If not you can add this to it:

if [ -d "$HOME/bin" ]; then
    PATH=$HOME/bin:$PATH
fi

if [ -d "$HOME/.local/bin" ]; then
    PATH=$HOME/.local/bin:$PATH
fi

GNU ln supports the -r option which allows using relative paths with ease. See ln(1).

---

Another option would be using the special field %k in the Exec setting as an argument. This field expands to the location of the running .desktop file. Note that according to the spec it may be an URI or a path.

[Desktop Entry]
Version=1.0
Name=Test
Exec=bash -c 'desktop_file=${1#*://}; dir=$(dirname "$(readlink -f "$desktop_file")"); echo "$dir"; sleep 1000' -- %k
Terminal=true
Type=Application

${1#*://} strips the protocol part in case %k expands to a file:// URI.