To extend the features of this blog I had to write a working pingback client supporting auto discovery of target links in a blog entry, auto discovery of pingback-server url to those targets and actually performing an xmlrpc pingback-ping request. As I was unable to find any small scripts performing that task alone without using a huge xml library to do that I did a quick'n'dirty approach on one single file, no includes whatsoever, achieving this goal.
It's usable as a web based cgi script, you enter a URL of any blog post and it will scan that post for targets. Those targets
will receive a pingback with the URL of your blog post. They will usually then go and check whether your post really contains
a link to their article and grab some text of your post to add it to their pingback description. This client has however no
control over what the server might do with the request. You can easliy automate the request by calling the script with
two variables (pass & sourceURI) via http get ( f.e. http://your.server/path/pingor.php?pass=your+pass& sourceURI=http://your.blog.server/path/post.html ).
Calling via Commandline is possible, too, just use sourceURI as parameter.
http://www.hixie.ch/specs/pingback/pingback - Pingback Specification