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Re: Design question(s), re: why use of tmp-files or named-pipes(/dev/fd/N) instead of plain pipes?

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From "Chris F.A. Johnson" <chris@cfajohnson.com>
Newsgroups gnu.bash.bug
Subject Re: Design question(s), re: why use of tmp-files or named-pipes(/dev/fd/N) instead of plain pipes?
Date Sat, 17 Oct 2015 22:19:38 -0400 (EDT)
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On Sat, 17 Oct 2015, Linda Walsh wrote:
> Chet Ramey wrote:
>> On 10/16/15 7:52 PM, Linda Walsh wrote:
>> 
>>> As I mentioned, my initial take on implementation was
>>> using standard pipes instead of named pipes (not having read
>>> or perhaps having glossed over the 'named pipes' aspect).
>> 
>> I think you're missing that process substitution is a word expansion
>> that is defined to expand to a filename.  When it uses /dev/fd, it
>> uses pipes and exposes that pipe to the process as a filename in
>> /dev/fd.  Named pipes are an alternative for systems that don't support
>> /dev/fd.
> -----
> 	??? I've never seen a usage where it expands to a filename and
> is treated as such.

Try this:

echo <(cat /etc/passwd)


-- 
Chris F.A. Johnson, <http://cfajohnson.com>

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Re: Design question(s), re: why use of tmp-files or named-pipes(/dev/fd/N) instead of plain pipes? "Chris F.A. Johnson" <chris@cfajohnson.com> - 2015-10-17 22:19 -0400

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