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copied!<p>One easy solution is to use:</p> <pre><code>ssh localhost "(cd /tmp && nohup sleep 10) >/dev/null 2>&1 &" </code></pre> <p>(this also works if you use braces, see second example below).</p> <p>I did not experiment further but I am reasonably convinced it has to do with open file descriptors hanging around. Perhaps zsh and dash bind the <code>&&</code> so that this means what has to be spelled as:</p> <pre><code>{ cd /tmp && nohup sleep 10; } >/dev/null 2>&1 </code></pre> <p>in bash.<hr>Nope, quick experiment in dash shows that <code>echo foo && echo bar >file</code> only redirects the latter. Still, it has to have something to do with lingering open fd's causing ssh to wait for more output; I've run into this a lot in the past. <hr> One more trick, not needed if you use the parentheses or braces for this particular case but might be useful in a more general context, where the set of commands to do with <code>&&</code> are more complex. Since bash seems to be hanging on to the file descriptor inappropriately with <code>&&</code> but not with <code>;</code>, you can turn <code>a && b && c</code> into <code>a || exit 1; b || exit 1; c</code>. This works with the test case:</p> <pre><code>ssh localhost "true || exit 1; echo going on; nohup sleep 10 >/dev/null 2>&1 &" </code></pre> <p>Replace <code>true</code> with <code>false</code> and the echo of "going on" is omitted.</p> <p>(You can also <code>set -e</code>, although sometimes that is a bigger hammer than desired.)</p>

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