Re: [MIT-Scheme-devel] Running interactive subprocess

[Taylor R Campbell]

   Date: Mon, 02 May 2011 20:13:17 -0300
   From: "Diogo F. S. Ramos" <address@hidden>

   I am trying to run an interactive subprocess but I'm having troubles
   communicating with it.

   The subprocess in question is mplayer, which accepts single keystrokes.

   I've played with the (run-shell-command) options but I can't get it to
   correctly send the chars to the subprocess.

You probably want to use the lower-level (undocumented) subprocess
support -- RUN-SHELL-COMMAND and RUN-SYNCHRONOUS-SUBPROCESS always
create pipes or a pty for the subprocess's standard input, output, and
error, and run it in a new session; the subprocess never sees Scheme's
controlling terminal directly.

Try

(run-subprocess-in-foreground
 "/path/to/mplayer"
 '#("mplayer" "--whatever" "--arguments" "--you" "want")
 '#("environment=variables" "set=like so"))

This will return a subprocess object once the subprocess's status
changes -- either when the subprocess exits normally, terminates on a
signal, or stops.  You can use SUBPROCESS-STATUS to find its status,
and SUBPROCESS-EXIT-REASON to find its exit value, if it exited
normally; the number of the signal that caused it to terminate; or the
number of the signal that caused it to stop.

If that doesn't work, show your code -- specify exactly what you
typed, exactly what you saw, and exactly what you expected to see.