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From: Clark Wang <dearvoid@gmail.com>
Newsgroups: gnu.bash.bug
Subject: Re: cat<(echo text) not same as cat <(echo text)
Date: Mon, 4 Jun 2018 16:40:12 +0800
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On Mon, Jun 4, 2018 at 11:48 AM, Edward Huff <ejhuff@gmail.com> wrote:

> That is unexpected.
>

I agree it may look "unexpected" because "cat<file" is the same as "cat
<file". But for "cat<file", '<' is part of input/output redirection but '<'
in "cat<(echo text)" is not. Instead, "<(echo text)" is *process substition*
.

According to bash manual: "On systems that can support it, there is an
additional expansion available: *process substitution*. *This is performed
at the same time as tilde, parameter, variable, and arithmetic expansion
and command substitution.*"

-clark