2.2 Region File
The region file is an ASCII text file that is used to store the region names. It contains one or more region names that are separated by line feed/carriage return "\LF\CR\" or comma ",". If the region file contains zero region names, no region information will be read and all POP entries in the phonebook file will be without region information.
The first line in the file MUST be an integer that is represented as an ASCII string and that denotes the number of region names in the region file. If the first line in the file contains non-numeric characters, all POP entries in the phonebook will be ignored. If this value is less than the number of region names, then the region names at the index greater than this value MUST be ignored. If the value is greater than the number of region names, then all region names MUST be read.
All the following lines in the file MUST contain the region name, one region per line.
The maximum length of a region name MUST be 31 characters. All ASCII characters MUST be allowed in the region name.
If the length exceeds 31 characters, the first 31 characters MUST be read as the region name and the remaining characters MUST be ignored.