Hi,

another thing which has bitten me going from PTYs to pipes
(specifically because I wanted to have stderr in a separate
channel - that part worked nicely), is that the callee "sees"
that, thinks "oh, I'm not being called interactively [1] and
disables line buffering.

Interactivity goes out of the window. Not always welcome :-)

I "solved" that by invoking the callee through stdbuf. I didn't
know this even existed before. And it's ugly [2] and won't work
always. I don't dare yet to use that in other than toy applications
(and, of course, to get yourself out of the occasional hard
spot).

Cheers

[1] probably the classical isatty(3) dance.
[2] it basically works by sneaking itself into LD_PRELOAD
   Not that I'm not thankful for someone providing that,
   mind you. But it's not the typical "for production"
   thing, I'd say.

 - t