PDI - Notes
The file names are those from the UNIX environment in which
this program was developed.
Ada package specifications and bodies are separated.
The file naming convention is as follows:
the main procedure and all package specifications are in name.a,
where the procedure or package is name.
Package and task bodies are in file name_body.a,
where the package or task is name.
The code is formatted with keywords in uppercase, identifiers
in lowercase, which was a common code formatting convention in 1990.