* Expects two additional arguments, a file name for the input and a file
* name for the output file. These two names must normally be distinct.
* An exception is made for the special name "-" which can be used in either
* Expects two additional arguments, a file name for the input and a file
* name for the output file. These two names must normally be distinct.
* An exception is made for the special name "-" which can be used in either