[fpc-pascal] hello world

[M Pulis]

Folks:

Apologies for the beginner nature of this query...

why won't this compile? It is the only open file and is saved, looks  
like a main program to me.

program Hello;

begin
   writeln ('Hello, world.');
   readln
end.


getting:

No main program found in open files. Can not build.


thanks!