┌────────────────────────────────────────────────────┐
│                   File Sorter.                     │
└────────────────────────────────────────────────────┘

SORTFILE expects the user to supply a filename, which
can include a directory pathname, as well as the start
position and length of the field on which the file is
to be sorted. 

The program first checks the size of the file and the
amount of free RAM available to see if it can be sorted
in memory. If it is too large, the file is sorted in
place. This method, which is far slower, allows the
file to be of any size up to 4 Gigabytes.