operating system (OS) detection in Lua

getOS.lua

function getOS()
	-- ask LuaJIT first
	if jit then
		return jit.os
	end

	-- Unix, Linux variants
	local fh,err = assert(io.popen("uname -o 2>/dev/null","r"))
	if fh then
		osname = fh:read()
	end

	return osname or "Windows"
end

I used this to play a sound using the command each OS provides:

• afplay on macOS
• play on Linux
• idc about Windows

https://github.com/TheBlckbird/neovim-config/blob/master/lua/sounds.lua:

local M = {}

local function getOS()
  -- ask LuaJIT first
  if jit then
    return jit.os
  end

  -- Unix, Linux variants
  local fh, err = assert(io.popen("uname -o 2>/dev/null", "r"))
  if fh then
    Osname = fh:read()
  end

  return Osname or "Windows"
end

function M.play(sound_file)
  vim.schedule(function()
    local command = ""
    if getOS() == "OSX" then
      command = "afplay"
    elseif getOS() == "Linux" then
      command = "play"
    else
      return
    end

    command = command .. " " .. sound_file .. " &"

    os.execute(command)
  end)
end

return M

This is a terrible solution for CLI apps, it re-opens and re-initializes conout 4-5 times in a row, leading not just to a seizure-flashing console windows, but also to all kinds of bugs down the road