IO::Select can_read/can_write timeout question

avo has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks, I have a question about sockets. I have a tcp/ip client that is using non-blocking socket object and IO::Select object to read and write when it is good time for it. I was wandering what would an ideal timeout time for can_read() and can_write() be. I would like to report immediately when the connection is bad. I am doing the following at the moment:

if($socket->can_read(0.3)) { readstuff ... } else { raise error... }

The environment where I will be using this client is Wireless 11mbs network.

I noticed that some times although the remote host is not offline - the 0.3 timeout looks too little.

Edit: g0n - code tags

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Re: IO::Select can_read/can_write timeout question by ikegami (Patriarch) on Nov 16, 2006 at 15:26 UTC
If you can both read and write from the socket, I wouldn't use `can_read` and `can_write` at all. I'd use `IO::Select::select($sel, $sel, undef, $timeout);` I'm assuming you close the connection or "ping" the other end on timeout. If not, you can simply use `IO::Select::select($sel, $sel);`	[reply] [d/l] [select]
Re: IO::Select can_read/can_write timeout question by salva (Canon) on Nov 16, 2006 at 17:12 UTC
Set the SO_KEEPALIVE option on your socket and let your OS do the hard work for you! `use Socket qw(SOL_SOCKET SO_KEEPALIVE); setsockopt($socket, SOL_SOCKET, SO_KEEPALIVE, 1);` [download]	[reply] [d/l]
Re: IO::Select can_read/can_write timeout question by kabeldag (Hermit) on Nov 22, 2006 at 13:32 UTC
Check out my adventures into IO::Select : chargen program is too slow / IO::Select socket handle outputting timing issue :-) Or maybe have a look at my Scratchpad.	[reply]