title: How open default terminal instead of using `xterm` ? is it safe to use ${TERM}?
body: <p>I want to run steam on linux, and I don't want to install xterm, there are two moments when does it want xterm</p>
  
  <pre><code>echo -e "$*" &gt;$tmpfile
  xterm -T "$title" -e "cat $tmpfile; echo -n 'Press enter to continue: '; read input"
  rm -f $tmpfile 
  </code></pre>
  
  <p>and</p>
  
  <pre><code># Fall back to sudo in a terminal
  xterm -e sudo -p "$prompt
  [sudo] password for user: " $*
  </code></pre>
  
  <p>is it safe for posix to use ${TERM} instead of xterm here?</p>