Why do you need that?
Note that the epoch vary between systems (Windows/MacOS/Linux/etc.), so such timestamp is mostly useful to compute diff between two dates.
Here is a way to see current time in timestamp format:

1. Date d = new Date();
2. println(d.getTime());

I'm also wanting the same thing. The reason is to save files that won't be overwritten because of name duplication, and frameCount isn't granular enough. I'm assuming an epoch stamp would guarantee uniqueness.

However, when I run the code above (either in draw, or via multiple static runs), minutes go by before I see any change in the return value. Here it is in draw():

1. void draw() {
2. Date d = new Date();
3. println(d.getTime());
4. }

What am I missing? Shouldn't I get a different result every frame? I've looked at the Java docs also, but There's something fundamental I guess I'm not understanding.

Of course, if there's a better way to assign unique identifiers, I'm open to that as well. But I wouldn't mind knowing what's going on with this too.

Many thanks.

It doesn't seem to change, because it is displayed with scientific notation, so it hides the low digits.
Try: println(d.getTime() % 1000); instead...
Alternatively, you can use millis() (time since start of sketch), System.currentTimeMillis() or even System.nanoTime().

" frameCount isn't granular enough"
You save several files per frame? You can also have your own counter...

Thanks, that helps.

"You save several files per frame? You can also have your own counter..."

Actually, 2 files per frame, but only on demand. The sketch I'm working on is a lumbering beast, getting maybe 1fps. That's ok, because fast animation is not what it's about. But I do have a lot of key and some mouse interaction, and it's fine (for now) if it only refreshes a lazy eye-blink later.

However, I do want the option to save an image and save all parameters in a text file, the latter which can be reloaded later to recreate the same results. The image and this preferences file need to have the same identifiers. I have most of this worked out. Envision something like 0123456789.jpg and 0123456789.txt as the matching file pair.

As I explore the image possibilities, I want to capture points of interest in the program and be able to recreate the same conditions later by loading a saved prefs file, which is cataloged and referenced by the saved image, all in a sub-directory within the sketch folder. Again, I've mostly got all that (still working on the prefs load, but I think I understand the process).

If these are named by frameCount or other runtime dependent indices, the chance increases that saved files will get overwritten eventually in subsequent work. If I explore and get to a point of interest fairly routinely within 3 to 5 minutes of playing around, eventually I'll press save at the same count as an earlier jaunt. It may be a slim chance, but I'm wanting to guarantee a non-destructive process.

Unlike making a movie from a single runtime, I will be saving files from across multiple runtimes, as well as multiple instances from a single runtime. That's why I'm trying to figure out how to ensure each file name is unique, regardless of when it's saved during a given runtime.

Too much information, I realize, for what is really a small problem. But I'm grateful for the insight into the timestamp values I was seeing. I might create my own date stamp with YearMonthDayMinuteSecondMilli, or some similar. Again, thanks!

Indeed, your way makes sense...
If you format the file name along the date / time, it reduces the risk of collision, and if it is correctly formatted, it will be easier to sort the files and interesting to see when it has been created. I am not sure a precision down to the milli is necessary...

In case you don't know, here is how to format the current date to a string:

1. DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd@HH_mm_ss");
2. Date d = new Date();
3. String fileName = formatter.format(d);
4. println(fileName);

Of course, you can change freely the separators, or remove them altogether.

I want to converte this output to unix time stamp but I can´t find out how... It´s the current system date with zero hours/minutes/seconds.  Can someone help me with an example? Would be very appreciated!

Best regards!