/sys$common/syshlp/helplib.hlb PASCAL, /ENVIRONMENT[=file-spec] D=Determined by attributes  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  /NOENVIRONMENT

  Controls whether the compiler produces an  environment  file  in
  which  declarations  and definitions made at the outermost level
  of a compilation unit are saved.  If the file-spec  is  omitted,
  the  default  file  name  is the same as the source program; the
  default  file  type  is  .PEN,  an  abbreviation   for   "Pascal
  Environment."

  You can provide a different name for  the  environment  file  by
  including  an  OpenVMS file specification after the /ENVIRONMENT
  qualifier, as in /ENVIRONMENT=MASTER.PEN.

  The /ENVIRONMENT qualifier overrides the  ENVIRONMENT  attribute
  in  the  source program or module.  You can use the /ENVIRONMENT
  qualifier to  suppress  the  creation  of  an  environment  file
  dictated  by  an ENVIRONMENT attribute, or to change the name of
  an environment file specified by an ENVIRONMENT attribute.

  By  default,  the  attributes  in  the  source  file  or  module
  determine  whether  an environment file is produced; however, if
  the /ENVIRONMENT qualifier is  specified  at  compile  time,  an
  environment file will always be created.

  Compaq Pascal accepts environment files that were  created  with
  previous  versions  of the compiler.  However, programs compiled
  with  previous  versions  of  the  compiler   may   not   accept
  environment  files  created  by  the  current  version of Compaq
  Pascal.