Re: foo | tee /dev/stderr | bar # << thanks!

[Greg Wooledge]

On Mon, Jul 06, 2020 at 09:45:59PM -0400, Dale R. Worley wrote:
> bug-bash@trodman.com writes:
> >     foo | tee >(cat >&2) | bar
> 
> I do wonder how portable >( ... ) is in practice, versus the portability
> of /dev/stderr.  Maybe I worry about the former because I'm not
> practiced in named-FIFO programming and so think of it as non-universal.

On Linux and BSD systems, >( ) will use a /dev/fd/ entry.  On most
commercial Unix systems, where /dev/fd/ does not exist, it will use a
named pipe in /var/tmp.  On a hypothetical system where neither one is
available (Microsoft Windows?), I believe it may use a temp file.  That
decision is made at bash's compile time.

The semantics of /dev/fd/* and named pipes are not quite identical, so
if you're relying on some very *special* mechanisms, then there could
indeed be portability issues.  For most scripts, however, it shouldn't
matter.