Sometimes it is necessary to get the filename of an object that is only known by the Object ID. This is possible for all objects of type WPDatafile and its childs classes.
For example, the classes WebExplorer_Url (WARP 3) and WPUrl (WARP 4) are children of the WPDatafile class. Therefore objects of both classes are represented by a file. The URL referenced in this objects is saved in this file as plain ASCII string and is identified by the WPS setup string LOCATOR. The only way to retrieve this URL using plain REXX is, as far as I know, to read the file.
To get the filename for an object referenced by an Object ID you can either use Henk Kelder's WPTOOLS-DLL or you can create an empty directory, copy the object into that directory (using SysCopyObject) and get the filename (using SysFileTree).