iphone :client-server communication not occuring - iphone

Question

i had made the following programming for client server programming but it is not working. the server is not able to receive the request for connection setup.plz help.
#import "clientserverprogramViewController.h"
#import "secondview.h"
#import <CoreFoundation/CFSocket.h>
#include <sys/socket.h>
#include <netinet/in.h>
NSInputStream *iStream;
NSOutputStream *oStream;
#implementation clientserverprogramViewController
#synthesize name,filepath,display;
-(IBAction) print {
NSString *urlStr = serverIP;]
[display setText : urlStr];
if (![urlStr isEqualToString:#""]) {
NSURL *website = [NSURL URLWithString:urlStr];
if (!website) {
NSLog(#"%# is not a valid URL");
return;
}
NSHost *host = [NSHost hostWithName:[website host]];
[NSStream getStreamsToHost:host port:3000 inputStream:&iStream outputStream:&oStream];
[iStream retain];
[oStream retain];
[iStream setDelegate:self];
[oStream setDelegate:self];
[iStream scheduleInRunLoop:[NSRunLoop currentRunLoop]
forMode:NSDefaultRunLoopMode];
[oStream scheduleInRunLoop:[NSRunLoop currentRunLoop]
forMode:NSDefaultRunLoopMode];
[iStream open];
[oStream open];
}
}
-(IBAction) settings {
[self presentModalViewController:nextview animated: YES];
}
-(IBAction) cancel {
exit(0);
}
- (void)dealloc {
[super dealloc];
}
#end

Answer 1

You only open streams and don't do anything with them. It's like picking up a phone and not dialing a number. Use NSStreamDelegate protocol to implement data transmission code.
Update:
You have these lines that set the delegate for streams:
[iStream setDelegate:self];
[oStream setDelegate:self];
Now implement methods that are defined in NSStreamDelegate protocol in your own class (AFAIK - there's only one of them). See how to receive/send data from there.

Answer 2

Is there a specific reason you're using streams?
What about using NSURLConnection? Here's a piece of code from a project of mine. Both are in KANetworkManager. KANetworkTransactionType is simply a enum that helps me know how to parse the response.
+ (void) createAndStartUrlConnection:(NSMutableURLRequest *)request type:(KANetworkTransactionType)type target:(id)target callback:(SEL)callback;
{
[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
NSDictionary *requestDict = [NSDictionary dictionaryWithObjectsAndKeys:request, #"request", [NSNumber numberWithInt:type], #"type", target, #"target", [NSValue valueWithPointer:callback], #"callback", nil];
[KANetworkManager performSelectorInBackground:#selector(makeNetworkCall:) withObject:requestDict];
}
I'm able to made a synchronous network call because I always call this method on its own thread. It's a simpler way to achieve asynchronous network communications without dealing with delegates (although the delegate method provides some benefits). Your parseResponse method would need to be specific to whatever your web service it sending back. parseResponse would notify the callback method. Let me know if you have additional questions regarding this.
+ (void) makeNetworkCall:(NSDictionary *)params
{
// We assume this method won't be called from the main thread, so we need our own NSAutoreleasePool.
NSAutoreleasePool *autoreleasePool = [[NSAutoreleasePool alloc] init];
NSMutableURLRequest *request = [params objectForKey:#"request"];
KANetworkTransactionType type = [(NSNumber *)[params objectForKey:#"type"] intValue];
id target = [params objectForKey:#"target"];
SEL callback = (SEL)[[params objectForKey:#"callback"] pointerValue];
NSURLResponse *response;
NSError *err;
// We make a synchronous request assuming we're on a background thread.
NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&err];
if (data.length > 0)
{
[self parseResponse:data type:type target:target callback:callback];
}
else
{
NSLog(#"Error occured during network call. %#", err);
}
[autoreleasePool drain];
}

Answer 3

JB gates,
In your code you inform iStream and oStream that your clientserverprogramViewController object is to be the delegate for each. However, a proper delegate needs actual implementation. Your class needs to implement this method:
– stream:handleEvent:
The details are documented here:
Reading From Input Streams
Writing To Output Streams
Also, your code will not work on a real iPhone. There is an updated Core Foundation API for creating the socket pair, details here.
Update
Just wondering if this is not a software issue but maybe the server is behind a firewall. Please give details what the server is, ie webserver, netcat, or simple TCP socket, etc.
Peter