Shell Scripts – How to Run an Application for a Set Time

Here are the steps:

1. Creating the interactive caller script

Since you want to execute the script and then have the terminal remain in an interactive mode, we need to use a special caller script, which in turn requires expect. We'll assume the script you want to execute is called test.sh

• Install expect with sudo apt-get -y install expect

• Create the caller script with this format:

  #!/usr/bin/expect -f 
  
  spawn -noecho bash           # create a shell
  expect "$ "                  # wait for prompt
  send "cd /path to script\n"  # your script directory
  send "./test.sh\n"           # your script name
  interact                     # switch to interactive mode
  

• Make the caller script, say call_test.sh, executable with

  sudo chmod +x /path/to/call_test.sh

2. Creating the Launcher

• Press Alt+F2, and type gksudo gedit /usr/share/applications/TestSH.desktop, where TestSH is whatever you want to call your launcher icon.

• The file is of the following form:

  [Desktop Entry]
  Version=1.0          # your script version
  Type=Application
  Terminal=true        # you want a terminal, so...
  StartupNotify=true
  Icon=                # can be a built-in (/usr/share/icons)
                   # or a custom file, SVG or PNG
  Name=TestSH          # Whatever you want to call it
  Comment=           # description
  Exec=/path/to/call-test.sh # Path to caller script
  Categories=Application;
  

• Finally, make sure the actual script is executable, with sudo chmod +x /path/to/test.sh

• Close the editor, and search for "TestSH" (script name) in the HUD; you will see the icon, which you can click on, and also drag to the launcher or desktop to add it there.

Open the file explorer Files. Press Alt+F10 and select Preferences. You should see something like this.

In the Behavior tab, select Ask each time and close it. Now double on a shell script will ask you what to do each time. If you want to straight away execute the script, select the first option Run executable text files when they are opened.