part of the ArsDigita Community System, by Jon Salz, taken from http://openacs.org/doc/acs-developer-support/ :
Our development environment previously consisted largely of Emacs, and tail -f /web/servername/log/servername-error.log. Now this has been augmented: ad_footer and ad_admin_footer now display a link entitled Developer Information. (You can use the ds_link procedure to generate the link yourself.) Following the link displays a screenful of information including:
In addition, the ClientDebug facility of AOLserver 2 has been re-implemented in the abstract URL system (which serves nearly all non-static pages). If an error occurs while serving a page, a stack trace is printed out.
Note that these nifty features pop up only when you are logged in as a site-wide administrator! Revealing this information to anyone else would pose a huge security risk.
Your comment will show up at the bottom of the page, beneath the Developer Information link (but only for site-wide administrators). It will also be displayed on the Developer Information page itself.ds_comment "Foo is $foo"
Comments are displayed even if an error occurs in the page!
Note that you may not want to enable this stuff for production systems - they probably incur a slight performance hit (although this hasn't been benchmarked).[ns/server/yourservername/acs/developer-support] ; remember information about connections, for developers' benefit? EnabledP=1 ; remember information about every database request? DatabaseEnabledP=1 ; remember information for which client hosts? EnabledIPs=* ; remember this information for how long? sweep how often? (in seconds) DataLifetime=900 DataSweepInterval=900
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