title: How to call bash commands from tcl script?
body: <p>Bash commands are available from an interactive tclsh session. E.g. in a tclsh session you can have</p>
  
  <pre><code>% ls
  </code></pre>
  
  <p>instead of</p>
  
  <pre><code>$ exec ls
  </code></pre>
  
  <p>However, you cant have a tcl script which calls bash commands directly (i.e. without <code>exec</code>). </p>
  
  <p>How can I make tclsh to recognize bash commands while interpreting tcl script files, just like it does in an interactive session?</p>
  
  <p>I guess there is some tcl package (or something like that), which is being loaded  automatically while launching an interactive session to support direct calls of bash commans. How can I load it manually in tcl script files?</p>