The ENVIRONMENT attribute can be applied  to  compilation  units
  and  causes  the unit's program or module level declarations and
  definitions to be saved.

  Syntax:

     ENVIRONMENT [[( name-string )]]

  If the 'name string' is omitted, the name of the source file  is
  used  as  the  environment  file name with the default file type
  PEN.

  The declarations and definitions made at the outermost level  of
  the compilation unit (provided they do not have the AUTOMATIC or
  HIDDEN attribute) are saved in a newly created environment file.
  If  the  name string is specified, you must include a legal file
  specification.

  See the "HP Pascal Language Reference Manual" for  the  complete
  description of using the ENVIRONMENT attribute.