It comes with the software. No fishiness required. Use:

`cds_root irun`/bin/cdnshelp

or maybe if it's really old:

`cds_root irun`/tools/bin/cdnshelp

You'll find the documentation in there. Note the quotation marks are backwards single quotation marks - the cds_root irun command tells you the installation path to where irun is found from.

Andrew.