This manual page documents briefly the checklink command, a.k.a. the W3C
Link Checker.

checklink is a program that reads an HTML or XHTML document, extracts a
list of anchors and lists and checks that no anchor is defined twice and
that all the links are dereferenceable, including the fragments. It warns
about HTTP redirects, including directory redirects, and can check
recursively a part of a web site.

The program can be used either as a command line tool or as a CGI script.