Perl

Socket Receive String Until Specific Byte Value is Received

Demonstrates the Chilkat Socket ReceiveStringUntilByte method. Perl

use chilkat();

$success = 0;

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

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

# --------------------------------------------------------------------
# This example uses the public TCP echo service at https://tcpbin.com/
# --------------------------------------------------------------------

$useTls = 0;
$port = 4242;
$maxWaitMs = 5000;
$success = $sock->Connect("tcpbin.com",$port,$useTls,$maxWaitMs);
if ($success == 0) {
    print $sock->lastErrorText() . "\r\n";
    exit;
}

# Wait a max of 2 seconds for a response..
$sock->put_MaxReadIdleMs(2000);

# Send some strings, each terminated by a 0 byte.
$sock->SendString("This is the 1st string");
$sock->SendByte(0);
$sock->SendString("This is string number 2");
$sock->SendByte(0);

# The tcpbin.com echo server only echoes after receiving an LF (linefeed char)
$sock->SendByte(10);

# Now let's receive what is echoed back....
# Receive each string and the NULL byte.
# The call to ReceiveStringUntilByte will receive incoming data until the lookForByte is encountered.
# The lookForByte is receive and discarded (it is not returned in the string)
$lookForByte = 0;
$s1 = $sock->receiveStringUntilByte($lookForByte);
if ($sock->get_LastMethodSuccess() == 0) {
    print $sock->lastErrorText() . "\r\n";
    exit;
}

print $s1 . "\r\n";

$s2 = $sock->receiveStringUntilByte($lookForByte);
if ($sock->get_LastMethodSuccess() == 0) {
    print $sock->lastErrorText() . "\r\n";
    exit;
}

print $s2 . "\r\n";

# The echo server will also echo back the final LF
$sock->ReceiveByte(1);
$maxWaitMs = 100;
$sock->Close(100);

# Output:
# This is the 1st string
# This is string number 2