Linux WSL

Ubuntu Pengwin

• lsb_release -a per Checking your Ubuntu Version
• cat /etc/*release works for most distributions.
• ppa:jonathonf/vim, vim-gtk3, packaging files are based on "latest" Debian/Ubuntu if a more recent version of Vim is required than provided in Ubuntu.
• sudo hwclock --hctosys resets system time to hardware clock time: sudo apt update error: "Release file is not yet valid".

apt

When sudo apt update && sudo apt upgrade produces a warning similar to:

5 packages can be upgraded. Run 'apt list --upgradable' to see them.

...

The following packages have been kept back:
  cloud-init libruby3.0 python3-update-manager ruby3.0 update-manager-core
0 upgraded, 0 newly installed, 0 to remove and 5 not upgraded.

Update the packages individually.

sudo apt list --upgradable
sudo apt install --only-upgrade <package name>

Fedora RHEL

• cat /etc/os-release provides detailed version information.

bash script

• Minimal safe Bash script template describes m-radzikowski/script-template.sh.
• bashew bash script creator - from small stand-alone script to complex projects with CI/CD and testing describes pforret / bashew.

  VAR is:	unset	empty	non-empty
  [ -z "${VAR}" ]	true	true	false
  [ -z "${VAR+set}" ]	true	false	false
  [ -z "${VAR-unset}" ]	false	true	false
  [ -n "${VAR}" ]	false	false	true
  [ -n "${VAR+set}" ]	false	true	true
  [ -n "${VAR-unset}" ]	true	false	true

• Associative Arrays

  declare -a toinstall
  for key in "${!package_to_install[@]}"; do
    if [[ $(command -v $key) ]]; then
      IO:debug "${package_to_install[$key]} is already installed."
    else
      toinstall=(${toinstall[@]} ${package_to_install["$key"]})
    fi
  done