Re: process substitution stdout connected to pipeline

[Greg Wooledge]

On Fri, Feb 13, 2015 at 05:10:42PM +0000, Pádraig Brady wrote:
> bash though seems to connect the stdout of the process substitution
> to the pipeline, which seems like a bug:
> $ : | tee >(md5sum) | sha1sum
> 253a7a49edee354f35b2e416554127cf29c85724  -

md5sum inherits the anonymous pipe to sha1sum as its stdout, because
that's how child processes work.  I don't see it as an error in bash,
but rather in the script.  You might want a construction like:

: | tee >(md5sum >&2) | sha1sum

Then you have md5sum writing to bash's stderr, and sha1sum writing to
bash's stdout.  Or you could get fancier with things like 3>&1.