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the bash terminal

These notes need a big recompile. They were a frustrated response to bash terminal colorization, so reminiscent of fighter pilots turning off all the display clutter in their HUDs.

green and black perhaps?

• Context: A PC running the Terminal application
  • Tab: Ubuntu (a user-friendly distribution built on Debian Linux)
    • There is but one Linux kernel… and many ornamentations including Ubuntu
    • Association: Windows Subsystem for Linux version 2 (WSL-2)
    • bash: the command line interface to Linux, access to operating system services
  • Tab: ssh to a cloud VM; similar issues
• Screen text is a lot of (unpleasant) colors: both in bash and the vim editor
  • ls produces a lot of colorizing
  • Plus the command prompt is complicated
• I might enjoy a black screen, green text, and a prompt like (active-env) cloud$

rewrite paused here…

• Top-of-window bar > clean spot > right click > Settings
• Use the left sub-topic menu to go through and customize everything that looks worth the bother
• Create a new color scheme, re-name it, make green the foreground, set it to default
• issue the command ls -al .bash* to see bashrc-related files

historical version here down

• Comment out these lines in .bashrc

# enable color support of ls and also add handy aliases
#if [ -x /usr/bin/dircolors ]; then
#    test -r ~/.dircolors && eval "$(dircolors -b ~/.dircolors)" || eval "$(dircolors -b)"
#    alias ls='ls --color=auto'
#    #alias dir='dir --color=auto'
#    #alias vdir='vdir --color=auto'
#
#    alias grep='grep --color=auto'
#    alias fgrep='fgrep --color=auto'
#    alias egrep='egrep --color=auto'
#fi

• Command line: source ~/.bashrc
• Check with ls -al again

Terminal: cloud VM

green text

For green text type this on the command line: echo -e "Default \e[32mDefault"

prompt fix

The prompt’s job is to tell me which computer I am entering commands on (and possibly whether I am working inside a conda environment).

• Edit ~/.bashrc' in vi, scroll past the $PS1` stuff
  • $PS1 is a variable for the default bash prompt
• Add this line:

PS1="my computer> "

• Command line: source ~/.bashrc

Now the prompt tells me when I am working on my local machine. For VMs: Use simple but instructive prompts in like fashion.

A conda environment name will be prepended to this bash prompt. By default this prompt will be (base) my computer> . This is ok by me: When I switch environments by means of conda activate some-environment the prompt will automatically change the prompt to (some-environment) my computer>.

ls fix

To change the colors of the text produced by ls check an online resource like this. The bare-bones to make directory names green is like so:

• dircolors -b >> .bashrc appends the current ls color scheme to .bashrc
• edit .bashrc and go to the end of the file
• Observe the dense text we just added:

LS_COLORS=`rs=0:di=01;34....etcetera etcetera etceters....;export LS_COLORS`

• These are key-value pairs.
• The color green is ‘32’ so find the entry for di (directory) and set it to di=01;32.
• source ~/.bashrc
• ls -al

vi fix

vi is an ancient text editor with arcane syntax inherited from an even older editor called ed. vim is the modern version of vi.

To disable a profusion of colorized text in vi: In escape mode type :syntax off.

To disable a profusion of colorized text permanently:

vi ~/.vimrc

<escape>
G
o
syntax off
<escape>
:wq

• Re-run vi to verify this worked