The iocsh command
dbl * "RTYP PREC EGU DTYP DESC"
emits a comma-separated list of quoted field values for the listed fields, but completely ignores the fields that don't exist for a particular record type. The results are difficult to parse; fields that don't exist should at least be given an empty place-holder. They can be distinguished from empty fields by the quotes.
While working on this, also make sure that the output is properly escaped (there's a libCom function for that) so that the output for string fields that contain double-quotes can still be parsed properly.