Hello,

how do you write an equivalent of

$ cmdA | cmdB | cmdC

in Ruby?

Specifically, I would like to see the PID, return value and stderr of
each of these commands but I would like cmdB to read the stdout of
cmdA directly, on its stdin, and similarily for cmdC and cmdB.

Here I am not interested in feeding cmdA some particular input (eg. it
can read /dev/null for all I care) but in general gluing arbitrary fd
to its stdin might be desirable in other cases.

Thanks

Michal