How can I specify which port to use in Perl's IO::Socket::INET?
I am using IO::Socket::INET to create inter-process communication in my program. I need to use a specific port number in my TCP cli开发者_如何转开发ent. I was following the example in Perl doc, but it doesn't work. Here is my code:
old code(working):
tx_socket = new IO::Socket::INET->new('127.0.0.1:8001') || die "Can't connect to 127.0.0.1:8001 : $!\n";
new code(not working):
tx_socket = new IO::Socket::INET->new('127.0.0.1:8001', LocalPort=>9000 ) || die "Can't connect to 127.0.0.1:8001 : $!\n";
Does anyone know what's wrong?
Grant McLean's answer works, if you fix the missing comma, but "works" here may be relative to what you are expecting.
use IO::Socket::INET;
$sock = IO::Socket::INET->new(
PeerAddr => '127.0.0.1',
PeerPort => 8001,
LocalPort => 9000,
Proto => 'tcp'
);
die("No socket!\n") unless $sock;
print "Socket good!\n";
Running this yields:
No socket!
Which isn't because the code doesn't work, it's working as expected (in my case). That is, it's expected that a connection to a localhost port 8001 will fail with nothing listening on the other side. This illustrates the usefulness of error reporting:
use IO::Socket::INET;
$sock = IO::Socket::INET->new(
PeerAddr => '127.0.0.1',
PeerPort => 8001,
LocalPort => 9000,
Proto => 'tcp'
) or die("$!\n");
die("No socket!\n") unless $sock;
print "Socket good!\n";
Which running now yields:
Connection refused
If I run netcat listening on port 8001, I get a different result:
Socket good!
According to the documentation, you should be doing something like:
$sock = IO::Socket::INET->new(
PeerAddr => '127.0.0.1',
PeerPort => 8001,
LocalPort => 9000,
Proto => 'tcp'
) or die "Connect error: $!";
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