Learning command line

This is a documentation I do to keep myself organized in my stydies.

Here I am going to write only the things that were new to me, when I was going through the tutorial. Find full tutorial by following this LINK.

It took me 3 hours total within 2 days to complete this tutorial:

Terminal keyboard shortcuts

One of the common ways to edit the line is to use Control key (usually Ctrl or ⌃).

• ⌃ + A => get to the begging of the line immidiately
• ⌃ + E => get to the end of the line immidiately
• ⌃ + U => clears the begging of the line and let’s you start over immidiately
• for multi-line text use ⌥ + mouse pointer click to navigate to the specific place in your text
• ⌃ + L => does the same thing as clear command

Manipulating files

Here’s the list of the commands that I did not know about earlier:

• diff => used for the comparison of files that are similar but not identical

  Here’s an example:

  $ diff sonnet_1.txt sonnet_1_lower_case.txt
  < That thereby beauty's Rose might never die,
  ---
  > That thereby beauty's rose might never die,
  

• mv command, which is short for ‘move’ is used to rename files as well.

  The code below would rename the file test to test_file.txtz:

    $ echo "test text" > test
    $ mv test test_file.txt
    $ ls
    test_file.txt
  

• use -f (‘f’ for ‘force’) to override the implicit -i option

• use -h option when listing files in a given directory to have “human-readable” view on the files. This will basically change size in bytes to kilobytes:

  RBM-DNAIDA-A01:commandLineTasks dnaida$ ls -hl
  total 256
  -rw-r--r--  1 dnaida  staff    93K May 29 21:37 sonnets.txt
  

Inspecting files

I really liked the command curl which allows you to download content from any given URL.

This way I was able to download the HTML content from my website homepage https://www.dmytronaida.com, save it to a file on my machine and open in browser window all from the terminal:

RBM-DNAIDA-A01:commandLineTasks dnaida$ curl https://www.dmytronaida.com > site.html
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  6416  100  6416    0     0  72548      0 --:--:-- --:--:-- --:--:-- 72909
RBM-DNAIDA-A01:commandLineTasks dnaida$ ls 
site.html		sonnet_1_complete.txt	sonnets.txt
RBM-DNAIDA-A01:commandLineTasks dnaida$ chrome site.html 
-bash: chrome: command not found
RBM-DNAIDA-A01:commandLineTasks dnaida$ open ./site.html 
RBM-DNAIDA-A01:commandLineTasks dnaida$ 

• head => shows the first 10 lines of the file
• tail => shows the last 10 lines of the file

• wc => word, line, and byte count for a given file

  RBM-DNAIDA-A01:commandLineTasks dnaida$ wc sonnets.txt 
    2620   17670   95635 sonnets.txt
  

• less => allows backward movement in the file as well as forward movement.
  • when, scanning through a file using less command:
    • f for ‘forward’ one page
    • b for ‘back’ one page
    • /<string> for searching matching keywords in file

Working with directories

• open => open files and directories with the default program
• cd - => brings you back to the previous directory, whatever it was