I keep a on line record of changes I have made to these packages. One main purpose of CDBS is to indicate to the user what set of reference files to use if the user wishes to re-process his or her observations. Tattler Tattler is a Python script that compares a directory tree to a CVS repository and reports the differences to the site administrator.
Fits is a portable image format supported by all major astronomical analysis packages.
The gethelp script allows iraf help to be viewed in a web browser by converting help files to html on the fly. The gasp package supports astrometry using the Guide Star Survey scans. The synthetic photometry package computes the predicted flux seen through the HST for a specified target and observing mode. The flux can either be output as a function of wavelength or integrated over a passband. The XC and mkpkg tasks are part of the iraf distribution and are used to compile source code in a portable manner.