/fopen should contain the encoding switch. $read can detect this automatically or at least make a good guess. $read always reads the entire file up to a specific line. $read will read the entire file if no line is specified.
There is no way to select the OUTPUT encoding with /write or /fwrite. Though with /fopen /fwrite should use the specified encoding set with /fopen.
/fopen -e <encoding> <handle> <file path>
