bind a client connection

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

I have a *IX system with 2 NICs. I have a program that allows me to make a connection to an outside IP address using a socket. This works great except I need to bind to one of my local NICs so that I can go out over the VPN. For example: I have 192.168.199.100 and 200.172.15.40 as my IP addresses for the NICs. The VPN connections ALL use the 192.168.199.100 address but the *IX system will grab whichever NIC is not busy and most of the time it is the 200.172.15.40 address and I can not make a connection to the other side using that address. Without re-writing the code to use more update to date modules does anyone know of a way to get "use Socket"; to bind to a LOCAL IP address. Below is my "connecting" code that the program currently uses.

    $them = $opt_h;
    $iaddr = inet_aton($remote);
    $paddr = sockaddr_in($port, $iaddr);
    $proto = getprotobyname('tcp');

    socket(SOCKET, AF_INET, SOCK_STREAM, $proto) || die "socket error:
+ $!";

    print STDOUT "connecting...\n\n";
    if (connect(SOCKET,$paddr)) {
         print STDOUT "Connected to host: $them, port: $port\n\n";
    } else {
         die "socket error: $!";
    }
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Re: bind a client connection by wrog (Friar) on Feb 11, 2012 at 21:22 UTC
you can use `bind()` on outgoing connections, e.g., `bind(SOCKET, pack_sockaddr_in(0, inet_aton($local_ip)))` It's exactly the same as when you're setting up a server except that you're calling `connect` rather than `listen` (... and the point of using `pack_sockaddr_in` is so that you don't have to create extra variables you don't need. Unlike with `sockaddr_in` which looks at its context to see whether it should be packing or unpacking, `pack_sockaddr_in` always packs... and you could do that with the `connect()` call as well to get rid of `$iaddr` and `$paddr`...)	[reply] [d/l] [select]
Re^2: bind a client connection by Anonymous Monk on Feb 11, 2012 at 22:29 UTC
Or you can use IO::Socket::INET, much more civilized interface :)	[reply]
Re^3: bind a client connection by wrog (Friar) on Feb 12, 2012 at 00:25 UTC
Without re-writing the code to use more [up] to date modules	[reply]
Re^4: bind a client connection by Anonymous Monk on Feb 12, 2012 at 00:34 UTC
Re: bind a client connection by Anonymous Monk on Feb 10, 2012 at 21:23 UTC
That ought to work, provided $remove/$iaddr/$paddr contains the IP you want (192.168.199.100)	[reply]