Re: [Chicken-users] gnuplot subprocess: python->chicken

[Bryan Vicknair]

On Tue, Apr 30, 2013 at 08:29:37PM +0200, Peter Bex wrote:
> So you can fix this rather easily by calling (close-output-port o)
> before reading from stderr.

Wonderful, that did it.  For future searches of the archive, here is the final
solution::


    (use srfi-1 srfi-13 posix extras)

    (define cmd "
    set terminal pngcairo size 460,344 font 'Verdana,10'
    set output '/tmp/graph-scm.png'
    plot '-' using 1:2
    2012-09-23  0
    2012-09-30  24
    2012-10-07  63
    ")

    (define go
      (lambda ()
        (define-values (i o pid stderr) (process* "gnuplot"))
        (write-line cmd o)
        (write-line "exit" o)

        ; I have nothing more to say to you gnuplot, don't wait on me.
        (close-output-port o)

        (let ((err (read-string #f stderr)))

          ; I don't want to hear anything else you say gnuplot.  We're done.
          (close-input-port i)
          (close-input-port stderr)

          (when (> (string-length err) 0)
            (error err)))))

Also glad to have found your blog!


Bryan Vicknair