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Perl

Check Whether a Socket Is Writable

See more Socket/SSL/TLS Examples

Demonstrates Socket.CheckWriteable, which waits for the connected socket to become writable. It returns 1 if writable, 0 if it did not become writable before the timeout, or -1 on error.

Background. A maxWaitMs of 0 performs a nonblocking poll. This is useful for flow control before attempting a large send.

Chilkat Perl Downloads

Chilkat2 Perl
use strict;
use warnings;
use Chilkat2;

my $socket = Chilkat2::Socket->new;

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

# Wait up to 5 seconds for the socket to become writable.  Returns 1 if writable, 0 if it did not
# become writable before the timeout, or -1 on error.
my $writable = $socket->CheckWriteable(5000);
if ($writable < 0) {
    print $socket->LastErrorText, "\n";
    exit;
}

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

print "The socket is writable.\n";