title: Command substitution in U-Boot's hush shell
body: <p>Does the hush shell used in U-Boot support command substitution? I tried the usual bash-like ways, <code>$(command)</code> as well as the syntax with backticks, but neither seems to work in hush shell.
  What I'm trying to achieve is to find all variables starting with &quot;FOO_&quot; by <code>env grep -en '^FOO_'</code> and then iterate over these variables, performing some action on them. But so far I wasn't able to get the output of this command into a variable, so I cannot iterate over it.</p>
  <p>Does anyone know how to do this?</p>