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Perl

Wait for a Socket to Become Writable

See more Socket/SSL/TLS Examples

Demonstrates Socket.SelectForWriting, which waits for the socket, or sockets in a socket set, to become writable. It returns 1 if writable, 0 on timeout, or -1 on error.

Background. A timeoutMs of 0 performs a nonblocking poll. This is useful before attempting to send when the peer may be applying flow control.

Chilkat Perl Downloads

Perl
use chilkat();

$success = 0;

$socket = chilkat::CkSocket->new();

#  Connect to the server using TLS.
$bTls = 1;
$maxWaitMs = 5000;
$success = $socket->Connect("example.com",5000,$bTls,$maxWaitMs);
if ($success == 0) {
    print $socket->lastErrorText() . "\r\n";
    exit;
}

#  Wait up to 5 seconds for the socket (or sockets in a socket set) to become writable.  Returns 1 if
#  writable, 0 on timeout, or -1 on error.
$ready = $socket->SelectForWriting(5000);
if ($ready < 0) {
    print $socket->lastErrorText() . "\r\n";
    exit;
}

if ($ready != 1) {
    print "The socket did not become writable before the timeout." . "\r\n";
    exit;
}

print "The socket is ready for writing." . "\r\n";