[fpc-pascal] Converting old pascal written for Pascal/MT+ compiler

[Jacob Kroon]

Hi,

I have some old Pascal code that was compiled in a CPM environment using 
the Pascal/MT+ compiler from Digital Research. I'm trying to get this 
project to build in a modern environment, for a start using FreePascal.

First, is anyone aware of a tool for converting this dialect of Pascal 
to something that FreePascal will accept ?

Second, the old code contains a lot of:

var
foobar : external integer;

in sources that reference 'foobar', then there is a declaration in one 
of them:

var
foobar : integer;

As I understand it, in order to translate this to something that 
FreePascal understands, the variable needs to go in a "unit" and be part 
of its interface. Then, pascal sources that needs to reference the 
variable should use this unit. Is this the easiest way forward ?

I thought maybe I instead could adapt the syntax like:

var
foobar : integer; external;

but with this I still get undefined references when linking. Using units 
seems ok.

Bets regards
Jacob