Using CALL:
- CALL is used to invoke a PROCEDURE or SUBROUTINE from inside a macro.
- CALL requires the name of a procedure or subroutine followed by any parameters required.
```
STARTMACRO
  ...
  CALL MYPROC 7 {A=1,B=2,C=3} "Just another string"
  ...
ENDMACRO

PROCEDURE MYPROC L:MYNUM T:MYTABLE S:MYSTRING
  ...
RETURN
```
- It is not uncommon to see the same procedure called many times within a macro.
```
STARTMACRO
  ...
  WHILE <test>
    CALL APROC <parameters>
  ENDWHILE
  ...
ENDMACRO
```