[vox-tech] writing to a shell instance

[Norm Matloff]

Here's what I'd like to do.  I'm running code, in this case Python, in
xterm A (replace by your favorite terminal emulator), and want that code
to write to xterm B, just as if I had typed directly into xterm B.

Say for example I want to run the ls command in xterm B, but do so via
some action in A.  Say the latter is /dev/pts/8.  I could run the Python
code

import os
os.system('echo "ls" > /dev/pts/8')

I have 2 questions:

1.  How do I get the end-of-line character in there, so that the ls
command actually runs?  I've tried "ls\n", "ls \r\n" and lots of
variants, e.g.

echocmd = 'echo "ls'+chr(14)+chr(10)+'" > /dev/pts/13'
os.system(echocmd)

But no matter what I try, it doesn't work.  The "ls" does appear in
xterm B, and the newlines, but it's still expecting more input from me.
If I manually hit Enter in xterm B, then it works.

I know this must be simple ridiculously simple, but I don't see it.

Yes, I know I could use a pipe here, but I want to retain the ability to
manually type in xterm B, i.e. I want to be able to input there either
by physically typing there or by having the program in xterm B do it.

Maybe I can launch xterm A via a pipe in the first place?  I've tried
that a bit, but don't have enough experience with pipes to see how to
make that work either.

One solution is to use "screen," which is what I'm doing currently,
but some people would like to use my program from Windows.

2.  Which brings me to my next question:  How can I do this in Windows?
(Not Cygwin.)

Any ideas would be much appreciated.

Norm