Hi, I have an old and normally very reliable piece of code that sends mail via smtp. Currently a customer is having trouble with it: after it connects to the socket, it hangs while trying to read the first line. Using ethereal, I can see that the mail server is indeed sending me the first line, "220 ... \r\n". Connecting manually with telnet to the same server/port works perfectly, and the beginning ethereal output for the telnet connection looks the same as the perl script session to me.

I'm at a loss as to what could cause this. If it's a firewall or something like that, I think it would block the whole connection. I think a firewall would also block my manual telnet test.

I have two questions, really:
1. Can anyone think of a cause or explanation for this?
2. Do you think that rewriting my code to use IO::Socket might help?

This is a stripped down version of my code to illustrate what it does: 

my $smtp = '167.206.5.250';

# part 1, connect to server:
use Socket;
my $proto = (getprotobyname('tcp'))[2];
my $port  = (getservbyname('smtp', 'tcp'))[2];
my $smtpaddr = pack('C4',$1,$2,$3,$4) if ( $smtp =~ /^(\d{1,3})\.(\d{1
+,3})\.(\d{1,3})\.(\d{1,3})$/ );
socket(S, AF_INET, SOCK_STREAM, $proto) or die("socket failed: $!");
connect(S, pack('Sna4x8', AF_INET, $port, $smtpaddr)) or die("connect 
+failed: $!");;

# part 2, read first line:
local($oldfh) = select(S); $| = 1; select($oldfh);
while (my $line = <S>)
{
    print "--> $line\n";
    last;
}

[download]
Thanks,
Joe

P.S. I'm using perl 5.8.1 on windows, in case the version/os makes a difference here.

In reply to hung reading first line of socket by blahblahblah

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