macOS, Linux, OpenBSD等で画面の解像度を取得

get_resolution.sh

#!/usr/bin/env zsh

_has () {
  return $( whence $1 &>/dev/null )
}

getresolution () {
  # returns current resolution
  if [[ "$OSTYPE" == "darwin"* ]]; then
    system_profiler SPDisplaysDataType | awk '/Resolution:/{print $2 "x" $4}'
  elif _has xrandr; then
    xrandr | awk '/\*/{print $1}'
  elif _has xdpyinfo; then
    xdpyinfo | awk '/dimensions/{print $2}'
  fi
}

getresolution