(Objective-C) Socket Receive String Until Specific Byte Value is Received

Demonstrates the Chilkat Socket ReceiveStringUntilByte method.

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#import <CkoSocket.h>
#import <NSString.h>

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

CkoSocket *sock = [[CkoSocket alloc] init];

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

BOOL useTls = NO;
int port = 4242;
int maxWaitMs = 5000;
BOOL success = [sock Connect: @"tcpbin.com" port: [NSNumber numberWithInt: port] ssl: useTls maxWaitMs: [NSNumber numberWithInt: maxWaitMs]];
if (success == NO) {
    NSLog(@"%@",sock.LastErrorText);
    return;
}

// Wait a max of 2 seconds for a response..
sock.MaxReadIdleMs = [NSNumber numberWithInt:2000];

// Send some strings, each terminated by a 0 byte.
[sock SendString: @"This is the 1st string"];
[sock SendByte: [NSNumber numberWithInt: 0]];
[sock SendString: @"This is string number 2"];
[sock SendByte: [NSNumber numberWithInt: 0]];

// The tcpbin.com echo server only echoes after receiving an LF (linefeed char)
[sock SendByte: [NSNumber numberWithInt: 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)
int lookForByte = 0;
NSString *s1 = [sock ReceiveStringUntilByte: [NSNumber numberWithInt: lookForByte]];
if (sock.LastMethodSuccess == NO) {
    NSLog(@"%@",sock.LastErrorText);
    return;
}

NSLog(@"%@",s1);

NSString *s2 = [sock ReceiveStringUntilByte: [NSNumber numberWithInt: lookForByte]];
if (sock.LastMethodSuccess == NO) {
    NSLog(@"%@",sock.LastErrorText);
    return;
}

NSLog(@"%@",s2);

// The echo server will also echo back the final LF
[sock ReceiveByte: YES];
maxWaitMs = 100;
[sock Close: [NSNumber numberWithInt: 100]];

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