bug#1388: 23.0.60; Emacs shell problem with echo "1+1" | bc

[Stefan Monnier]

> I've installed a fix that sets process-connection-type to nil for
> every element of a pipeline but the first. Or do you think the first
> element should have p-c-t nil as well?

> Currently, the first/last elements in an eshell pipeline have:
> stdin = tty/non-tty, stdout = tty/non-tty;
> whereas in a "real" shell pipeline they have:
> stdin = tty/non-tty, stdout = non-tty/tty;

> ie I chose to get the input right over the output.

Not sure if it's better in general.
Maybe we should just leave the code as is for now, but add a comment
explaining the problem.  For the longer term we can either try your
approach, or better try and come up with a way to make it work right
(i.e. extending start-process).


        Stefan