HP SunSoft Pascal 4.0 - Manual (Page 110)

86 Pascal 4.0 User’s Guide
5
Using extern
In the previous example, the extern definition for variables is put into an
include file and then shared. You can do the same for the extern procedure
definition. In doing so, you must also declare the variable with a define
declaration in the module that defines the procedure. This declaration nullifies
the effect of the
extern declaration.
The commands to compile and
execute
inc_prog2.p and
inc_mod2.p
hostname% pc -xl inc_prog2.p inc_mod2.p
inc_prog2.p:
inc_mod2.p:
Linking:
hostname% a.out
From MAIN, before PROC: 1
From PROC : 1
From MAIN, after PROC : 2
The program unit, ext_prog.p program ext_prog;
%include "extern.h";
begin
global := 1;
writeln('From MAIN, before PROC: ',global);
proc;
writeln('From MAIN, after PROC: ',global);
end. { ext_prog }