PROGRAM

 A program is a set of instructions  that  can  be  compiled  and
 executed by itself.

 Syntax:

    [[attribute-list]] 
    PROGRAM comp-unit-identifier [[({file-identifier},...)]];
      [[declaration-section]]
      BEGIN
      {statement};...
      END.


 The 'attribute-list' is one or  more  identifiers  that  provide
 additional information about the compilation unit.

 The 'comp-unit-identifier' specifies the name  of  the  program.
 The  identifier  appears  only  in  the heading and has no other
 purpose within the compilation unit.

 The 'file-identifier' specifies the names of any file  variables
 associated with the external files used by the compilation unit.

 The 'declaration-section' is a VSI Pascal declaration section.

 The 'statement' is any VSI Pascal statement.

 The program  heading  includes  all  information  preceding  the
 program  block.   If  your  program contains any input or output
 routines, you must list all the external file variables that you
 are  using  in  the  compilation unit's heading.  File variables
 listed in a heading must also be declared locally in the  block,
 except for the predeclared file variables INPUT and OUTPUT.

 The INPUT identifier corresponds to a predefined  external  file
 that  accepts  input  from  the  default  device  (usually, your
 terminal); the OUTPUT identifier  corresponds  to  a  predefined
 external  file that sends output to the default device (usually,
 your terminal).

 If you redeclare INPUT or OUTPUT in a  nested  block,  you  lose
 access to the default input or output devices.