Write stderr on iPhone to both file and console

Question

I\'m following the suggestion in the answer here for redirecting NSLog output on an iOS device to a file, which works great. The problem is that it no longer shows up in the co

Answer 1

Or you can redirect to a TCP socket and view on a remote telnet client. No need for XCode this way!

Basically:

1. Create a standard C function which calls an Obj-C static method:

   void tcpLogg_log(NSString* fmt, ...)
   {
       va_list args;
       va_start(args, fmt);
       [TCPLogger tcpLog:fmt :args];
       va_end(args);
   }
   

2. The static Obj-C method:

   (void)tcpLog:(NSString*)fmt :(va_list)args
   {
       NSLogv(fmt, args);
   
   if(sharedSingleton != nil && sharedSingleton.socket  != nil)
   {
     NSString *time = [sharedSingleton.dateFormat stringFromDate:[NSDate date]];
     NSString *msg = [[NSString alloc] initWithFormat:fmt arguments:args];
     mach_port_t tid = pthread_mach_thread_np(pthread_self());
   
     NSString *str = [NSString stringWithFormat:@"%@[%X]: %@\r\n", time, tid, msg];
     NSData *data = [str dataUsingEncoding:NSUTF8StringEncoding];
     [sharedSingleton.socket writeData:data 
                             withTimeout:NETWORK_CLIENT_TIMEOUT_PERIOD 
                             tag:0];                                                
   }
   
   
   }
    

3. Then in your .pch file, add the following lines to override NSLog()

   define NSLog(...) tcpLogg_log(__VA_ARGS__); 
   void tcpLogg_log(NSString* fmt, ...);
   

Of course more details are required to handle the TCP Socket. Working source code is available here: https://github.com/driedler/iOS-TCP-Logger/wiki/About