Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.java.programmer > #10539

Re: Theads and FTP

Show all headers | View raw

On 12/5/2011 9:58 AM, Andreas Leitgeb wrote:
> Arne Vajhøj<arne@vajhoej.dk>  wrote:
>> On 12/4/2011 4:14 PM, Daniel Pitts wrote:
>>> On 12/3/11 8:31 PM, Roedy Green wrote:
>>>> I have watched FTP voyager work. It seems to have at least two threads
>>>> simultaneously uploading downloading. You might think what's the
>>>> point. You can be transferring while you are waiting for the server
>>>> to open or close a file and send back confirmation.
>>>> I was wondering if this is done by logging on twice and having two
>>>> completely independent sessions, or if FTP itself has some multithread
>>>> ability.
>>> Why not look up the RFC on the FTP protocol?
>>> I seem to recall that it inherently uses two sockets, one for the
>>> commands and one for transfers. I don't know if the command stream is
>>> allowed (or expected) to be active during a transfer, I haven't read the
>>> spec myself in quite a while.
>>> Also, you don't necessarily need multiple threads to handle multiple
>>> connections. In posix c "select()" is use to manage multiple connections.
>
>> I believe it is possible to write a FTP client single threaded even
>> without select.
>
> Ok there's of course also poll(), and one could set all channels to
> non-blocking mode and do a more or less(with sleep) busy loop iterating
> through all the channels and see which of them have data...
>
> Did you mean one of these, or was it a serious statement?

Serious.

At least for some simple FTP client cases I believe it is
possible for the app to know what connection to read from
when.

Arne

Back to comp.lang.java.programmer | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Theads and FTP Roedy Green <see_website@mindprod.com.invalid> - 2011-12-03 20:31 -0800
  Re: Theads and FTP Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2011-12-04 13:14 -0800
    Re: Theads and FTP Arne Vajhøj <arne@vajhoej.dk> - 2011-12-04 22:06 -0500
      Re: Theads and FTP Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2011-12-05 14:58 +0000
        Re: Theads and FTP Arne Vajhøj <arne@vajhoej.dk> - 2011-12-05 22:01 -0500
          Re: Theads and FTP Tom Anderson <twic@urchin.earth.li> - 2011-12-06 21:07 +0000
    Re: Theads and FTP Roedy Green <see_website@mindprod.com.invalid> - 2011-12-05 05:33 -0800
      Re: Theads and FTP Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2011-12-05 09:29 -0800
      Re: Theads and FTP Joshua Cranmer <Pidgeot18@verizon.invalid> - 2011-12-05 12:29 -0600
        Re: Theads and FTP Joshua Cranmer <Pidgeot18@verizon.invalid> - 2011-12-06 11:28 -0600
      Re: Theads and FTP Arne Vajhøj <arne@vajhoej.dk> - 2011-12-05 22:00 -0500
      Re: Theads and FTP Tom Anderson <twic@urchin.earth.li> - 2011-12-06 22:16 +0000
  Re: Theads and FTP Arne Vajhøj <arne@vajhoej.dk> - 2011-12-04 22:04 -0500

csiph-web