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    Not a concern with pbcopy, but worth mentioning in general: whatever the process substitution outputs is also seen by the next pipe segment, after the original input; e.g.: seq 3 | tee >(cat -n) | cat -e (cat -n numbers the input lines, cat -e marks newlines with $; you'll see that cat -e is applied to both the original input (first) and (then) the output from cat -n). Output from multiple process substitutions will arrive in non-deterministic order. Commented Dec 9, 2014 at 4:47
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    The >( only works in bash. If you try that using for instance sh it won't work. It's important to make this notice. Commented Dec 16, 2014 at 16:31
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    @AAlvz: Good point: process substitution is not a POSIX feature; dash, which act as sh on Ubuntu, doesn't support it, and even Bash itself deactivates the feature when invoked as sh or when set -o posix is in effect. However, it's not just Bash that supports process substitutions: ksh and zsh support them too (not sure about others). Commented Apr 15, 2015 at 2:59
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    @mklement0 that doesn't appear to be true. On zsh (Ubuntu 14.04) your line prints: 1 1 2 2 3 3 1$ 2$ 3$ Which is sad, because I really wanted the functionality to be as you say it. Commented Oct 21, 2016 at 9:56
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    @Aktau: Indeed, my sample command only work as described in bash and ksh - zsh apparently doesn't send output from output process substitutions through the pipeline (arguably, that's preferable, because it doesn't pollute what is sent to the next pipeline segment - though it still prints). In all shells mentioned, however, it's generally not a good idea to have a single pipeline in which regular stdout output and output from process substitutions is mixed - the output ordering will not be predictable, in a manner that may only surface infrequently or with large output data sets. Commented Oct 22, 2016 at 5:39