Convert text files EOF from CRLF to LF (windows to unix)

# make sure to install dos2unix: apt install dos2unix
# find .: Start the search in the current directory.
# -type d \( -name node_modules -o -name .git \) -prune: If a directory is named node_modules or .git, exclude it from the search.
# -o: Logical OR operator to continue the search for other files.
# -type f: Only consider regular files.
# -exec dos2unix {} +: Apply dos2unix to each file found.
find . -type d \( -name node_modules -o -name .git \) -prune -o -type f -exec dos2unix {} +

Copy / Sync files between directories

# -a: Archive mode, which preserves symbolic links, permissions, timestamps, and other attributes.
# --delete: Deletes files in the destination that are not in the source.
rsync -a --delete /path/to/source/ /path/to/destination/

Find hardware information

sudo dmidecode -t
sudo lspci

TTY and killing processes

# switching between tty terminals
Ctrl + Alt + F3 to F6

# get top running processes
top -n 1

# kill a process using a process id
pkill [xxxx]

# switch to graphical mode from ttyl
Ctrl + Alt + F7

Installing Nvidia driver on Debian based distributions

Follow Debian's wiki page on how to properly install the correct Nvidia driver for your card. The following are the primary simple steps to achieve it for most modern cards.

Check for any Linux header updates first and update the system before proceeding

apt install linux-headers-amd64

Add contrib, non-free and non-free-firmware components to /etc/apt/sources.list.

deb http://deb.debian.org/debian/ sid main contrib non-free non-free-firmware

Then run an update, install the necessary packages and reboot.

sudo apt update
sudo apt install nvidia-driver firmware-misc-nonfree
systemctrl reboot

After the installation is complete and the system reboots, check if the Nvidia driver is running.

nvidia-smi

Loading modules at boot time

If there are any modules you need to run at boot time (for instnance sensor control modules for fans, etc), edit the following file and add them as needed.

sudo nano /etc/modules

Installing fonts

Download fonts from https://www.nerdfonts.com/font-downloads

Run the following commands:

# copy font files
sudo cp *.otf /usr/share/fonts/

# update font cache
sudo fc-cache -fv

Neovim init.vim and common shortcuts

Basic init.vim config for a common IDE layout:

set number
set autoindent
set tabstop=4
set softtabstop=4
set mouse=a
set expandtab
set shiftwidth=4
set smartindent
set cindent

call plug#begin()

Plug 'https://github.com/tpope/vim-fugitive' " Git branch info in airline
Plug 'https://github.com/vim-airline/vim-airline'
Plug 'https://github.com/preservim/nerdtree'
Plug 'https://github.com/tpope/vim-commentary'
Plug 'https://github.com/ap/vim-css-color' " CSS Color Preview
Plug 'https://github.com/rafi/awesome-vim-colorschemes' " Retro Scheme
Plug 'https://github.com/preservim/tagbar' " Tagbar for code navigation, requires `apt install exuberant-ctags`

call plug#end()

autocmd VimEnter * botright split | terminal /bin/bash
autocmd VimEnter * resize 10
autocmd VimEnter * NERDTree | wincmd p
autocmd VimEnter * if argc() > 0 | wincmd p | endif

" Forcing focus back to opened file
autocmd VimEnter * execute "normal \<C-w>\<C-w>"

" Key bindings
nmap <F8> :TagbarToggle<CR>
nnoremap <C-t> :NERDTreeToggle<CR>
nnoremap <C-f> :NERDTreeFind<CR>
noremap <C-n> :NERDTree<CR>

" let mapleader = "/" " default is /
let g:airline_detect_paste=1
let g:airline_theme='dark'

" Show buffer number with file name in airline tab bar
let g:airline#extensions#tabline#enabled = 1
let g:airline#extensions#tabline#buffer_nr_show = 1

Most common and useful Neovim shortcuts and commands:

Shortcut/Command	Description
/	search for a string
dd	deletes a while line
x	deletes a character
i	go into insert mode
Ctrl + O	navigate back
Ctrl + I	navigate forward
Ctrl + ^	toggle between next/previous buffer
0	beginning of line
$	end of line
%	toggle matching ) } ]
:s	substitude word in a line
:%s/old/new/gc	replace a word globally
G	go to end of file
gg	go to beginning of file
:!	execute command
:w	save file
:w myfilename	saves files with name
o	inserts a new line
e	move to next word
a	append to text
v	visual mode, highlight
y	yank (copy)
p	past (put)
:e	open file
:e .	open file explorer
:bn	next buffer
:bp	previous buffer
:terminal	opens default terminal
:split	opens file in split window
:resize 20	resizes window rows
:botright vertical 80vsplit file.py	open file in new window to the right 80 characters wide
Ctrl + \, Ctrl + N	back to normal mode
Ctrl + W, arrows	move focus between windows
:bd	deletes/removes a buffer within a window
:close	deletes/removes all buffers within a window

Local time issue with dual boot (Windows/Linux)

The local time seems to be inconsistent when switching between Windows and Linux. Running the following command on the Linux/GNU OS will fix the local time-sync issue.

sudo apt install ntpdate
sudo apt install ntp
sudo systemctl start ntpd

Custom bash functions

Sometimes you want to create and use custom functions globally in terminal. You can also reference this "bash bible" on GitHub for more useful scripts.

• Edit the ~/.bashrc file with your favourite text editor

  nano ~/.bashrc

• Add your custom functions at the end of the file
• Run the following command after updating your functions so it immediately takes effect

  source ~/.bashrc

Example: custom_split_url()

```bash
function custom_split_url() {
    printf "\n"
    printf "Splitting URL into query string param=value and URL decoding all values. Here are the results:"
    printf "\n\n"

    # Function to URL decode a string
    urldecode() {
        local url_encoded="${1//+/ }"
        printf '%b' "${url_encoded//%/\\x}"
    }

    # Function to add color to parameter names and subparameter names
    add_color() {
        local color_param="\033[0;33m"      # Yellow color for parameter names
        local color_subparam="\033[0;36m"   # Blue color for subparameter names
        local reset="\033[0m"               # Reset color

        if [[ $2 == "subparam" ]]; then
            printf "${color_subparam}%s${reset}" "$1"
        else
            printf "${color_param}%s${reset}" "$1"
        fi
    }

    # Input URL
    input_url="$1"

    # Extract parameters after "?" and decode them
    params=$(awk -F'[?&]' '{for(i=2;i<=NF;i++) {split($i, a, "="); printf("%s=%s\n", a[1], a[2])}}' <<< "$input_url")

    # Decode each parameter and print in a table format
    while read -r line; do
        param_name=$(cut -d'=' -f1 <<< "$line")
        param_value=$(cut -d'=' -f2- <<< "$line")

        # Split parameter value by commas and then decode individual values
        IFS=',' read -r -a values <<< "$(urldecode "$param_value")"
        for value in "${values[@]}"; do
            decoded_value=$(urldecode "$value")

            # Split subvalues by '&' sign and output each on a new line
            IFS='&' read -r -a subvalues <<< "$decoded_value"
            for subvalue in "${subvalues[@]}"; do
                IFS='=' read -r subparam_name subparam_value <<< "$subvalue"
                if [[ $subvalue == *"="* ]]; then
                    printf "%-35s %-35s\n" "$(add_color "$param_name" "param")" "$(add_color "$subparam_name" "subparam")=$subparam_value"
                else
                    printf "%-35s %-35s\n" "$(add_color "$param_name" "param")" "$subvalue"
                fi
            done
        done
    done <<< "$params"

    printf "\n"
}
```

Starting VirtualBox VM with a shortcut

Create an .sh file in your home bin folder with the following bash script, in this case the file will be called autostartvm.sh.

#!/bin/bash

# Include the name of the VM as well as which workspace you'd like it to open in
DESIRED_VMNAME="win11preview"
DESIRED_WORKSPACE=3

# Start the VirtualBox VM
VBoxManage startvm $DESIRED_VMNAME

# Wait for the VM window to appear (adjust sleep duration as needed)
sleep 1

# Find the window ID of the VM window
VM_WINDOW_ID=$(wmctrl -l | grep $DESIRED_VMNAME | awk '{print $1}')

# Move the VM window to the desired workspace
wmctrl -i -r $VM_WINDOW_ID -t $DESIRED_WORKSPACE

Make sure the file has execution permission:

chmod -x autostartvm.sh

Setup a keyboard shortcut in your OS environment that runs the following command:

bash /home/lin/bin/autostartvm.sh

Docker management

After installing Docker engine using Docker's official wiki based on your OS/distro, add your user to the docker user group:

sudo usermod -aG docker $USER

For listing images and containers as well as removing them, reference the following commands:

# list containers (-a shows non-active containers)
docker ps -a

# list images
docker images -a

# remove container
docker rm [container_name]

# remove image (remove associated containers first)
docker rmi [image_name] # remove docker image

# remove all images without at least one container associated to them
docker image prune -a

# autorize docker hub
docker login

# commit container changes to new image
docker commit <container_id> <new_image_name:tag>

# tag an image to a docker hub repository
docker tag local_image_name:new_tag docker_hub_username/docker_hub_repository:image_tag

# push docker image to docker hub
docker push docker_hub_username/docker_hub_repository:image_tag

# create docker image based on project Dockerfile
docker build -t <image_name> .

# run and start docker container; expose port 8080 to the host; mount volume.
# make sure the mounted volume directories exist in both the container and the host.
docker run -d -p 8080:8080 --volume $HOME/output:/app/output <image_name>

# access docker container shell in interactive mode
docker exec -it <container_id> /bin/bash

Drive and disk management

There will be times when you need to format a mounted disk. The following commands will help in those cases.

# list all detected disks
sudo fdisk -l

# launch terminal disk/partition management tool
sudo cfdisk

# format disk (in this case, the mounted drive is "sda")
sudo mkfs.ext4 /dev/sda

Mounting a secondary drive

You'll need to create a mounting point for the new drive. To do that, you need to create a directory for the drive and reference it as a mounting point to the drive's UUID in fstab.

# create a mounting point
sudo mkdir /mnt/backup_drive

# check if the drive is detected
sudo lsblk

# get the drive's UUID
sudo blkid

# add a mounting line in fstab. example line below:
# UUID="6EE6F9AB2ADC4697"    /mnt/backup_drive    ntfs    default 0 0
sudo nano /etc/fstab

# reboot system
systemctrl reboot

Mouse pointer acceleration

Some Linux/GNU distributions may default to enabling mouse pointer acceleration depending on your mouse/touchpad hardware. The following instructions will help disabling it as there is no graphical option to do it.

• Edit the file /usr/share/X11/xorg.conf.d/40-libinput.conf as root using your favourite text editor.

  sudo nano /usr/share/X11/xorg.conf.d/40-libinput.conf

• Add the following line under any sections with the words "pointer" or "touchpad" in the "Identifier" field:

  Option "AccelProfile" "flat"
  

  The following is an example section with the line added:

  Section "InputClass"
          Identifier "libinput touchpad catchall"
          MatchIsTouchpad "on"
          MatchDevicePath "/dev/input/event*"
          Driver "libinput"
          Option "AccelProfile" "flat"
  EndSection
  

Turning off wifi

The following commands will toggle wifi radio on/off if you want to simply rely primarily on a wired ethernet connection.

# turning off wifi radio
nmcli radio widi off

# turning on wifi radio
nmcli radio wifi on