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copied!<p>From <a href="http://www.gnu.org/software/bash/manual/bashref.html#Process-Substitution" rel="nofollow"><code>Process Substitution</code></a> </p> <blockquote> <p>The process list is run with <strong>its input or output connected to</strong> a FIFO or some file in <strong>/dev/fd</strong>. <strong>The name of this file is passed as an argument to the current command</strong> as the result of the expansion. If the >(list) form is used, <strong>writing to the file will provide input for list</strong>.</p> </blockquote> <p>What happens with <code>echo "test" >(wc)</code>?</p> <p>The file <code>/dev/fd/63</code> is opened for connecting <code>echo test</code> with <code>wc</code>. <code>wc</code> is started with it's input connected to <code>/dev/fd/63</code>. Then the name of this file (<code>/dev/fd/63</code>) is passed as an argument to the current command (<code>echo "test"</code>), resulting in <code>echo "test" /dev/fd/63</code>. This is why you see </p> <pre><code>test /dev/fd/63 </code></pre> <p>as output. <code>wc</code> waits for input, but since <code>echo</code> doesn't write to <code>/dev/fd/63</code>, the count will be <code>0</code>.</p> <p>If you want this to work, you must create a script, which takes the last argument and echos the first <code>N-1</code> arguments into the last </p> <pre><code>#! /bin/bash echo "${@:1:$(($# - 1))}" >${@: -1} </code></pre> <p>When you call this </p> <pre><code>bash script.sh test >(wc) </code></pre> <p>you will see the expected output </p> <pre><code>1 1 5 </code></pre>

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