HP SunSoft Pascal 4.0 User Manual

Page 97

Program Construction and Management

By default, both definitions of variable

are

public

. Thus, when you compile

and link the program and module units, references to

refer to the same

variable, as follows:

If you compile the program giving the

-xl

option, the variables are

private

by default, as follows:

You can get the same effect by explicitly declaring the variable in a

private

var

section. Similarly, when you use

-xl

, you can create

public

variables by

declaring them in a

public var

section.

As with routine declarations, it is often a good idea to declare

public

variables in an

include

file. Doing so makes it easier to keep your

declarations consistent.

There are other methods for making variables visible to different units. See
Chapter 5, “Separate Compilation,” for more information.

hostname% pc program_unit3.p module_unit3.p

program_unit.p:

module_unit.p:

Linking:

hostname% a.out

Hello, world for the 1 time.

Hello, world for the 2 time.

Hello, world for the 3 time.

Hello, world for the 4 time.

Hello, world for the 5 time.

hostname% pc -xl program_unit.p module_unit.p

program_unit.p:

module_unit.p:

Linking:

hostname% a.out

Hello, world for the 0 time.