One of the videos for today concerned using regular expressions with grep. Download the last file that was introduced now: wget https://courses.cs.washington.edu/courses/cse374/21sp/assignments/numberslist.
Write a grep command that identifies each of the phone numbers, regardless of the format of the number. Hint: find a pattern that matches one section, and then iteratively expand that pattern to be more general. Remember that you can match patterns exactly zero or one time (using ?), and that you can use a pipe to match one pattern OR another one.
man passwd or passwd --helpuseful.man chmod.top, and also ps, and jobs. Also hintbg, fg, kill do?If you have remaining time, revisit the exercises from Wednesday. It is likely that there is still some work to make a beautiful script!