There are five distinct property file types:

As indicated in Property files managed by the mergeprop utility table, one standard property file of each type is found in the OpenEdge-install-dir\properties directory.

Specifying the file type enables the mergeprop utility to process delta and target files appropriately. It also makes it unnecessary to explicitly identify the target file, unless you are operating on a copy or test file other than the standard file in the properties directory. The program can recognize "none" as a valid type and perform default processing, but you should provide a specific type as input.

The file type is expressed as an argument to the -type command switch.