These commands use the HTML rendering code that was written in 1995 by the Tcl group at Sun Microsystems that became Scriptics and Ajuba. The code does a great job in presenting simple documents with basic markups, but it does not compare to state-of-the-art browsers that properly handle frames, and more sophisticated features.
These commands are part of the Humelib package and can be imported from the namespace humelib.
Use of the HTML rendering code is subject to terms and conditions similar to the use of Tcl. See the file html_library.terms in the Humelib package directory.
package require Humelib namespace import -force humelib::* show_HTML_file /hume/components/dcc/dc_user_guide.html