Honestly, I have no idea, as I never tried that. Although I had large printouts, and it seems the oldest ones are lost, IIRC.
But for such long-running logs, you should use a real logger. For a primitive one (just appending given text to a text file), you can look at my e-mail sketch, which uses a simple logger. I added it to test logging after exporting to an application: that's another reason to use logs to text. Beside, once you get a text, you can use the search capabilities of your favorite text editor, etc.
Another advantage is that if your computer or your program stops working, you still have the log...

http://bazaar.launchpad.net/~philho/+junk/Processing/files/head:/_SmallPrograms/Email/

Hmm makes sense to use a text file logger. Honestly I didn't even need a the println commands. I just forgot to take one out before installing :) Though I went to take a look at the program. And nothing was broken. No errors, from Processing, I thought It was an out of memory kind of thing but all the programs on the computer were responsive including the sketch itself. So I am now confused and wondering what the problem could be. Did the mac mini I was using just got pissed off and decide to stop working?. I've had a similar thing happen to me with another installation about a year ago where it would just stop after a while with no errors or anything.

The program utilizes the Minim library and Arduino libraries? Are you aware of any weird time limitations for those? I'm kinda confused as to why that would happen.

I turned it off and on again and everything worked again so i'm confused...

I fail to understand what was the problem...
Do you mean your sketch just stopped working?
It can be an out of memory error, as a sketch run in its own JVM, which has its own memory settings (maximum memory, among others). If the program reaches the maximum memory, it stops with an out of memory error. Even if the other programs still have plenty of memory.
Java is garbage collected, but if some objects still have a reference on them (sometime from the JVM itself, eg. event handlers), they are never collected.
You can watch memory usage with JVisualVM.

Its ok that you fail to understand my problem because I fail to understand my problem. yea my sketch just stopped working. It just happened again apparently from a text i got. And if it was an out of memory error, I'd assume the program would crash? and give me some sort of error in the console right? I saw none of that. I will try increasing the maximum memory and try to do some work on checking it out. maybe download jVisualVM on that machine to see if there is anything. I'm just confused because I dont see any errors anywhere with the sketch or else where on the computer. Even if garbage isnt being collected i'd assume it would then crash at some point.

Oh well I'm gonna go look at this again if i find anything new and interesting I will be sure to make an edit to this post.

I think that the println window is limited

sweet but I'm not worried about that anymore though Chrisir. I thought the println limit was causing me problems with my sketch crashing due to memory errors but I realize that theres an unkown problem with that now where my sketch is stopping but not crashing.

You can increase the memory in processing in the settings (with ctrl-, I think)

hmm were you ever able to get around that problem with the end of the Loop?

This probably isn't helping for your sketch

hmm well damn. well I just got back from the installation. I had a couple return calls in the code that must have caused a problem once in a while. Its a loop of sounds that turn on different lights via arduino. I've heard the entire sound loop go through multiple times but it seems like it was choking every once in a while in a function and just returning. I dont know what else it could be but basically here are what I think the problem spots are. I'm not going to post the whole code because even though its not much it is 3 classes and it would just be a pain to put all that here. Here's my draw loop and the functions it references:

1. void draw() {
2.   if(isPlayingTheme){
3.     if(!themeSong.isPlaying()){
4.       // if playing the theme and its done...
5.       themeSong.pause();
6.       themeSong.rewind();//be kind, rewind :)
7.       int nextGroup = currSoundGroup + 1;
8.       currSoundGroup = nextGroup % soundGroups.length;
9.       am.allPinsWrite(0);// all arduino pins off before the next set of sounds
10.       println("theme done. next group");
11.       playSoundGroup();
12.       isPlayingTheme = false;
13.     }
14.     //return;//removed this return call and replaced it with an else
15.   }else{
16.    soundGroups[currSoundGroup].checkSounds();//check the status of the sounds playing every frame
17.   }
18.  
19. }
20. //start playing whatever the current sound group is
21. void playSoundGroup(){
22.   soundGroups[currSoundGroup].start();
23.  
24. }
25. void playTheme(){
26.   //println("playing theme");
27.   themeSong.play();
28.   am.allPinsWrite(0);// all arduino pins on for theme
29.   isPlayingTheme = true;
30. }

Here is the checkSounds() function that gets called at the end of draw. In the class of soundgroup which is a class around a group of AudioPlayer objects basically that play through once, call a theme song and then resets back to the start of the AudioPlayer list:

1.   void playSound(){
2.     sounds[currSound].play();
3.     println(getCurrentNum());
4.     //write data to the arduino manager about the current sound playing
5.     am.writeData(getCurrentNum(), "digital", 1);
6.   }
7.  
8.   void checkSounds(){
9.     if(!sounds[currSound].isPlaying()){
10.       sounds[currSound].pause();
11.       sounds[currSound].rewind();
12.       if(currSound == sounds.length - 1){
13.         //if reached end of sound list...
14.         currSound = 0;
15.         if(!isPlayingTheme) playTheme();
16.         //return;//removed this return as i think it was causing problems with the song list not being incremented sometimes
17.       }
18.       //turn off current sound pin before incrementing sounds
19.       am.writeData(getCurrentNum(), "digital", 0);
20.       currSound++;
21.       println("changing sounds :" + currSound);
22.       playSound();
23.     }
24.   }

removing those returns made it run again and hopefully fixed them. I dont know why they were causing problems though cuz they werent causing problems continuously. it may have been a weird overlap in actions/checks or something I'm honestly not really sure. I can post the whole sketch if need be to get some explanation.