Avoid conflict of ivar name with systemcall name

Source/GSAvahiRunLoopIntegration.h

@@ -43,7 +43,7 @@
 {
   NSRunLoop *runLoop;
   NSString *mode;
-  AvahiPoll *poll;
+  AvahiPoll *ap;
   NSMutableArray *children;
   NSLock *lock;
 }

Source/GSAvahiRunLoopIntegration.m

@@ -398,16 +398,16 @@ - (id) initWithRunLoop: (NSRunLoop*)rl
     }
   lock = [[NSLock alloc] init];
   [lock setName: @"GSAvahiRunLoopContextLock"];
-  poll = malloc(sizeof(AvahiPoll));
-  NSAssert(poll, @"Could not allocate avahi polling structure.");
-  poll->userdata = (void*)self; //userInfo
-  poll->watch_new = GSAvahiWatchNew; //create a new GSAvahiWatcher
-  poll->watch_update = GSAvahiWatchUpdate; //update the watcher
-  poll->watch_get_events = GSAvahiWatchGetEvents; //retrieve events
-  poll->watch_free = GSAvahiWatchFree; //remove watcher from context
-  poll->timeout_new = GSAvahiTimeoutNew; //create a new GSAvahiTimer
-  poll->timeout_update = GSAvahiTimeoutUpdate; //update the timer
-  poll->timeout_free = GSAvahiTimeoutFree; //remove the timer from context
+  ap = malloc(sizeof(AvahiPoll));
+  NSAssert(ap, @"Could not allocate avahi polling structure.");
+  ap->userdata = (void*)self; //userInfo
+  ap->watch_new = GSAvahiWatchNew; //create a new GSAvahiWatcher
+  ap->watch_update = GSAvahiWatchUpdate; //update the watcher
+  ap->watch_get_events = GSAvahiWatchGetEvents; //retrieve events
+  ap->watch_free = GSAvahiWatchFree; //remove watcher from context
+  ap->timeout_new = GSAvahiTimeoutNew; //create a new GSAvahiTimer
+  ap->timeout_update = GSAvahiTimeoutUpdate; //update the timer
+  ap->timeout_free = GSAvahiTimeoutFree; //remove the timer from context
   //Runloops don't need to be retained;
   runLoop = rl;
   ASSIGNCOPY(mode,aMode);
@@ -434,7 +434,7 @@ - (NSString*) mode
 
 - (const AvahiPoll*) avahiPoll
 {
-  return (const AvahiPoll*)poll;
+  return (const AvahiPoll*)ap;
 }
 
 - (GSAvahiTimer*) avahiTimerWithCallback: (AvahiTimeoutCallback)callback
@@ -539,16 +539,16 @@ - (void) dealloc
    * try to create additional watchers and timers on the runloop, so we should
    * clean it up properly:
    */
-  poll->userdata = (void*)NULL;
+  ap->userdata = (void*)NULL;
   [self removeFromRunLoop: runLoop
                   forMode: mode];
   FOR_IN(GSAvahiWatcher*, child, children)
     {
       [child setContext: nil];
     }
   END_FOR_IN(children)
-  free(poll);
-  poll = NULL;
+  free(ap);
+  ap = NULL;
   [children release];
   [mode release];
   [lock release];