In Processing, I set up the osc event method to receive a String from pd.

OscP5 oscP5;

String string;
int port = 12001;

void setup()
{
  oscP5 = new OscP5(this, port);
}

void draw()
{

}

void oscEvent(OscMessage message) 
{
  if (message.addrPattern().equals("/string"))
  {
     string =  message.arguments()[0].toString();
     println(string);
  }
}

How to send a string like "Hello, Processing!" to Processing?
I don't know

My Patch looks like this:

@RayManiac If I recall correctly, [oscformat] shouldn't have slashes for the arguments. (That's parallel to the way that [oscparse] removes slashes.) Try [oscformat string]...?

hjh

@RayManiac And the comma is a separator in Pd.
No commas in a string or it will be broken up at each comma.

You would need to build the message as decimal ascii and send it, and then convert back to ascii in Processing if the comma is really important.
David.

The slash is no problem, the comma and the white space are though. What @whale-av says is correct but you can do the conversion to ASCII and back to a symbol all in Pd. Here's how (separate the two messages, and combine them with the ASCII white space in between - 32):

I was checking out that backslash escape of the comma, and it looks like you can even escape the space character:
I wish I had known that earlier! Would've saved hours spent renaming wav files to not have spaces!

@jameslo I should have thought of the space escaping myself Avoiding spaces in file names is nevertheless a good practice IMHO.

@alexandros Yes. I did a small patch much like yours earlier, and another with makefilename escaping the backslash and the space.
It didn't seem worthwhile as an incoming message is usually unknown in advance.
I keep forgetting that it is now possible to type the escape character into a message.
After so many years frustrated by the impossibility I would hope that I would remember.
David.

Thank you, very much! Now I think, I can manage the Processing application myself.