HP SunSoft Pascal 4.0 - Manual (Page 104)

80 Pascal 4.0 User’s Guide
5
Using the
-xl
Option
When you use the – xl option, variables and top-level procedures and
functions declared in the program unit default to private . Look at the
difference when you compile and execute shrvar_prog.p and
shrvar_mod.p with – xl . See the source code in “Sharing Public Variables”
on page 77.
Without – xl , the variable global in shrvar_mod.p is treated as public ;
here, global is treated as private . Thus, the assignment:
global := global + 1;
is not reflected in shrvar_prog.p ; instead, each file uses its own private copy
of global .
The following sections describe five ways of sharing variables and routines
across units when you compile your program with –
xl .
Using public var Declarations
The following examples uses the public attribute in the var declaration to
make global public when you compile your program with –xl .
The commands to compile and
execute
shrvar_prog.p and
shrvar_mod.p with the –xl
option
hostname% pc -xl shrvar_prog.p shrvar_mod.p
shrvar_prog.p:
shrvar_mod.p:
Linking:
hostname% a.out
From MAIN, before PROC: 1
From PROC : 0
From MAIN, after PROC: 1