The functionality provided by FS_SPLIT_FILENAME and FS_JOIN_FILENAME is the same as that provided by the corresponding CBL_routines. In addition, using FS_SPLIT_FILENAME and FS_JOIN_FILENAME you can process filenames that specify Fileshare Server names using the $$server-name prefix at the front of the filename. When processing such filenames, the $$server-name prefix characters are included as part of the pathname parameter.
If you have included the callable sort, and receive error 173 after switching to release build, you need to include fhrsub.obj in your project.