How do I close a program from the terminal

Now every file is handled by another program say gedit and folders the same, so to kill [ the program handling that file or folder ] we can use two methods:

  1. The program name with:

    pkill <name_of_program>
    
  2. use of program PID (process id)

    • find the PID with pgrep <name_of_program>, then
    • kill it with kill <PID>

Information:

man pkill
man kill

Note: When closed this way any unsaved changes will be lost.