PSYC is about pushing information, and the notification of events is the most obvious application of that.

PSYC has realtime notification interfaces for software versioning system check-ins (see also CVS and GIT), syslog daemon events (see perlpsyc), Mediawiki edits, Phpbbs and Drupal message submissions and music titles playing now. All of these things can be brought to you in real-time rather than by e-mail or not at all.

Consider that all of these notifications aren't just pushed to you, they are multicast to all intentional recipients and you can control that using the subscription mechanisms.

See for the slides of the 2007 LinuxTag Berlin presentation Realtime IM/Chat Notification.

Developers, have a look at example code on the PHP page.


E-Mail notification

SMTP is a push technology with messages traveling our way rather than us having to look for them. Yet, during the 90s we stopped reading our mail on our mail servers, e-mail clients needed protocols to access our e-mails and now these e-mail clients periodically poll the server for new mail rather than receiving it in real-time. This introduces an unnecessary latency in e-mail conversation.

procmail can be used to forward a mail's author and subject line straight to PSYC, so at least you know when a new e-mail has arrived, immediately, and you can hit that "Get Mail" button.

See psycmail for more. See also mailcast for e-mail alerts that get redistributed to groups of subscribers by multicast rather than single recipients.

Generic update notifications

While for wikis the change of the article is itself the news, in regular newscasts updates are an originally not planned Internet phenomenon. News agencies used to write a story and maybe there's a follow-up story but not something like an update. This is yesterday's thinking. Today you first get the news out, at the same time you work on it - you research facts, you interview witnesses, you collect opinions. As time passes the freshness of the news is replaced by the quality of it.

The RSS format does not take this into account at all. You have to look out for little story title changes like Story... (Update), hopefully using the same webpage link, or even worse, you are confronted with an apparent new story with a new link and you have no way to figure out what the update actually was.

Atom is a bit smarter about this. It provides an atom:updated element which is only to be changed when a significant change has been made to the document. Still very rudimentary.

PSYC currently has either _notice_news_headline in a non-updating way, providing source, headline and link, or _notice_update derivates as in the examples on wikinotify. See also Newscasting.

It would be a logical step to bring news and updates together into a standardized syntax. It would come with a _degree_relevance of changes, which is finer than just major/minor as wiki and atom suggest, possibly a _degree_quality that indicates how satisfied the author is with the usability of the article (pretty low for an untrusted news source, rather high for a long-lived popular wikipedia article etc), as before a _summary of the changes and the _title of course.

Talking about summaries of changes - it may also be useful to have a standardized way to see the difference between documents, like cvs diff or wiki diff in a generic way for any kind of content. Oops, tough requirement!

One could think of more useful meta-information to send out in a newscast, like standardized categorization (politics, sports) and a _degree_importance of the story, so that you still get the absolute top news in sports even if you hate sports etc (I mean, a filter function could be applied to serve up only what you want to see).

Funny, atom provides an atom:category, but the content is not standardized. Also it has no qualifiers of relevance, importance or other like that. It provides a lot of information which is important to publishers, but irrelevant to readers - especially since they can click on the story and then find out about author and rights etc.

Hm, I'm a bit surprised that throwing a bit of thoughts in this direction already heads out beyond what RSS, Atom etc. have achieved. I thought smarter people than me have worked on that stuff. Maybe I didn't research well enough.

2010, Semantic Pingback is a kind of equivalent to PSYC's _notice done the HTTP way, with plenty of overhead and sounding really complicated. So finally the RSS world is catching up.

Updates about PSYC

Update/development notifications about PSYC software itself is usually sent to the psyc:// newscast place. You can /subscribe that.

Work in progress