Lua wait sleep

• 使用os.execute 执行涉及等待、超时的外部命令、程序。配合 >nul 不显示标准输出流信息。执行过程是阻塞（block）等待的。
  • os.execute"ping 1.1.1.1 /n 1 /w <time in milliseconds> >nul"  ，如os.execute"ping 1.1.1.1 /n 1 /w 1000 >nul" 。
  • os.execute"CHOICE /n /d:y /c:yn /t:1 >nul" 。
  • 为（Windows）系统安装GNU命令包（minGW？）。

>sleep --help
Usage: sleep NUMBER[SUFFIX]...
or: sleep OPTION
Pause for NUMBER seconds. SUFFIX may be `s' for seconds (the default),
`m' for minutes, `h' for hours or `d' for days. Unlike most implementations
that require NUMBER be an integer, here NUMBER may be an arbitrary floating
point number.

--help display this help and exit
--version output version information and exit

Report bugs to <bug-coreutils@gnu.org>.

进而可以 os.execute"sleep 1" 。

• 使用库。
  • require'socket'.select(nil,nil,sec) （9.4 – Non-Preemptive Multithreading - Programming in Lua）
  • require'luasocket'.sleep(sec) LuaSocket: Network support for the Lua language）

• • require'iuplua'.timer{TIME=millisec,action_cb=function()end}
• 整理参考：Easiest way to make lua script wait/pause/sleep/block for a few seconds? - Stack Overflow，avoid lua wait time loop while high cpu - Google 搜索，how to yield lua function idle when monitor file wait time high cpu - Google 搜索（useless），lua return yield cpu consume - Google 搜索（useless），Lua sockets - Asynchronous Events - Stack Overflow（LuaSocket + Lua Lanes/多线程、lua-ev）