Imposing a timeout on the <> operator - is this possible?

[Bob Dubery]

Hi all

I have code that polls a number of machines on our network and
retrieves stats from each one.

This is done via HTTP

This morning the program hung. When I started investigating I found
that one of the remote machines was in some kind of strange state. You
could ping it. You coud connect to it (HTTP, Telnet, FTP) but you got
no response.

So my program opens up a socket, fires off the HTTP request and then
waits for a response from apache, and waits, and waits, and waits...

The relevant portion of the code looks like this...

# open a socket...
$socket = IO::Socket::INET->new(PeerAddr => $netaddr,
PeerPort => 80,
Proto => "tcp",
Timeout => 10)
or die "Couldn\'t open the socket!!!!";

# form the HTTP request
$request = "GET $url HTTP\/1.0\n\n";

# request the file...
print $socket $request;

# process the output and strip out the response headers
$printit = 0;
# ...now read the socket and process the output
while($line = <$socket>){

# do some stuff with $line
}

The program hangs at the <> operator.

OK... a wierd situation and not a common one, but I want to improve
the code. Specificially when I invoke <> I'd like to be able to impose
a time out so that if I get nothing back after n seconds I can raise
an error condition and start interrogating the next site.

TIA

Bob Dubery

[JSM]

me******@hotmail.com (Bob Dubery) wrote in message news:<e8**************************@posting.google. com>...

OK... a wierd situation and not a common one, but I want to improve
the code. Specificially when I invoke <> I'd like to be able to impose
a time out so that if I get nothing back after n seconds I can raise
an error condition and start interrogating the next site.

You can use alarm to do this. There is an example in the Perl Cookbook (16.21).