Re: efficient timers

[Paul Merrell <marbux@...>]

On Sun, Apr 12, 2015 at 12:49 PM, Nagaev Boris <bnagaev@gmail.com> wrote:
> I have seen the following timers in Lua:
>
>  * posix.unistd.sleep [1]
>  * posix.time.nanosleep [2]
>  * posix.curses.napms [3]
>  * ngx.sleep [4]
>
> [1] https://luaposix.github.io/luaposix/modules/posix.unistd.html#sleep
> [2] https://luaposix.github.io/luaposix/modules/posix.time.html#nanosleep
> [3] https://luaposix.github.io/luaposix/modules/posix.curses.html#napms
> [4] http://wiki.nginx.org/HttpLuaModule#ngx.sleep

More that I've snipped from here and there:

Clean sleep method using a repeat … until loop, by Peter Odding,
<http://lua-users.org/lists/lua-l/2008-03/msg00213.html>

Large page of methods at <http://lua-users.org/wiki/SleepFunction>.

Suspend/resume a Lua script using coroutines:
<http://stackoverflow.com/questions/6145059/how-to-suspend-resume-processing-of-a-lua-command>

--- Delay for a number of seconds.
-- @param delay Number of seconds
function delay_s(delay)
    delay = delay or 1
    local time_to = os.time() + delay
    while os.time() < time_to do end
end

-- wait for a reply, using a custom timeout (set to 5 seconds here):


-- send HTTP request
strQuery =  "GET " .. strVersionUrlUri .. " HTTP/1.1\r\nHost: " ..
strVersionUrlHost .. "\r\n\r\n"
   net.write(nSocket, strQuery)
     t1 = os.time()
        -- read HTTP response
        strReply = ""
        bFirstRead = true
        nTimeoutSec = 5

        repeat
          if bFirstRead == true then
            repeat nSize, strChunk = net.read(nSocket)
              until strChunk ~= "" or os.difftime(os.time(), t1) > nTimeoutSec
          else
            nSize, strChunk = net.read(nSocket)
          end
          strReply = strReply .. strChunk
          bFirstRead = false
        until nSize <= 0

Best regards,

Paul


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