make-echo-stream input-stream output-stream → echo-stream

input-stream — an input stream.

output-stream — an output stream.

echo-stream — an echo stream.

Creates and returns an echo stream that takes input from input-stream and sends output to output-stream.

 (let ((out (make-string-output-stream))) 
    (with-open-stream 
        (s (make-echo-stream 
            (make-string-input-stream "this-is-read-and-echoed") 
            out)) 
      (read s) 
      (format s " * this-is-direct-output") 
      (get-output-stream-string out))) 
→ "this-is-read-and-echoed * this-is-direct-output"

echo-stream-input-stream, echo-stream-output-stream, make-two-way-stream