PHP: proc_open persistent file pointers

Is there a way to make the file streams returned by proc_open() persistent between page loads so I can make a PHP style interface to a terminal program?

Looking over the php functions it seems possible to make persistent pointers with stream_socket_client(<URL>, STREAM_CLIENT_PERSISTENT). But I don't think its possible to make a pointer to a terminal using a URL schema.

The other thing I can think of is to make a small C program to pipe output from stdin to a network socket and have PHP communicate with that.

http://dtach.sourceforge.net/

I did some kind of testing, but my PHP didn't have PTY support compiled in so I gave up. I do think this would allow it to work, however.