You can create a simple CGI in several languages, here is one in bash.
Just put this in your cgi-bin directory, call it w.cgi
The go to the url
http://address/cgi-bin/w.cgi
Code:
#!/bin/sh
echo "Content-type: text/html"
echo ""
echo "<html>"
echo "<head>"
echo "<title>Startup Mode</title>"
echo "<META HTTP-EQUIV=\"Pragma\" CONTENT=\"no-cache\">"
echo "</head>"
echo "<body bgcolor=\"#C0C0C0\" text=\"#000000\" link=\"#0000FF\" vlink=\"#C00000\" alink=\"#FFFF00\">"
echo "<center><h2>Output of w command</h2></center><p>"
echo "<pre>"
w
echo "</pre>"
echo "</body>"
echo "</html>"