CocoaAsyncSocket / GCDAsyncSocket add a delay between writes on the queue

Question

I have the following function:

if (socket==nil)
  socket = [[GCDAsyncSocket alloc] initWithDelegate:self delegateQueue:dispatch_get_main_queue()];
if (elBuffer==nil) 
  elBuffer = [[NSMutableData alloc] init];
}

if ([socket isDisconnected]) {
  NSError *err = nil;
  [socket connectToHost:elControlador.ip onPort:9761 error:&err]
}

[socket writeData:@"A01" withTimeout:30 tag:1];
[socket writeData:@"A02" withTimeout:30 tag:1];
[socket writeData:@"A03" withTimeout:30 tag:1];
[socket writeData:@"A04" withTimeout:30 tag:1];
[socket writeData:@"A05" withTimeout:30 tag:1];
[socket readDataWithTimeout:30 buffer:elBuffer bufferOffset:0 maxLength:-1 tag:1];

It works prefectly, except for the fact that the socket server needs a second or so between writes for it to work. I was wondering if anyone has run into the same problem and could shed a light on how to achieve this. Thanks.

Answer 1

I was able to get this to work using the following:

int i=0;
for(id aItem in aIDs) {
  NSString *directCommand = [NSString stringWithFormat:@"A%@",aItem];
  [self performSelector:@selector(fSend:) withObject:directCommand afterDelay:(2.0*i)];
  i++;
}
[socket readDataWithTimeout:30 buffer:elBuffer bufferOffset:0 maxLength:-1 tag:1];

-(void)fSend : (NSString *)aCommand {
  [socket writeData:aCommand withTimeout:30 tag:1];
}

This gives me a 2 seconds between performing the writeData without having to freeze the app and without flooding my equipment with writes.

Answer 2

If you want the client to wait between writing these strings:

• Put them into an array.
• Use a repeating NSTimer
• In the timer callback, write one line at a time until the array is exhausted, then invalidate the timer.