The MIF reader first scans the folder it is given for the MIF files defined in the mapping file. For each MIF file that it finds, it checks to see if it that file is requested by looking at the list of IDs specified in the mapping file. If a match is made or no IDs were specified in the mapping file, the MIF file is opened. The MIF reader then extracts features from the file one at a time, and passes them on to the rest of the FME for further processing. When the file is exhausted, the MIF reader starts on the next file in the folder.
Optionally a single MIF file can be provided as the dataset. In this case, only that MIF file will be read.