VMS Help FORTRAN, Logical Names  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  Various VMS logical names can be defined to modify the behavior of
  the Compaq Fortran compiler or an executing application.

1 - FORT$INCLUDE

  If defined during compilation, this logical name changes the
  default file specification used to locate include files and text
  libraries from '.FOR' and '.TLB' to 'FORT$INCLUDE:.FOR' and
  'FORT$INCLUDE:.TLB', respectively.  It can be a search list.

2 - FORT$LIBRARY

  If defined during compilation, this logical name specifies one or
  more default text libraries to be searched for library-based
  INCLUDE statements which do not specify a library file.  These
  default libraries are searched after any libraries specified on the
  command line (with /LIBRARY) and before the system-supplied library
  FORSYSDEF.TLB.  It can have multiple translations; each translation
  is used as if it appeared as an input file on the command line with
  the /LIBRARY qualifier with file specification defaulting occurring
  within the FORT$LIBRARY list only.

3 - FOR$ACCEPT

  If defined during execution, 'FOR$ACCEPT' is used instead of
  'SYS$INPUT' as the file specification for the implicit Fortran
  logical unit used for ACCEPT statements.

4 - FOR$CONVERTnnn

  If defined during execution, this logical name specifies a default
  data conversion type for unit "nnn".  The translation of the
  logical name must be a valid keyword for the /CONVERT= qualifier.
  For example:

      $ DEFINE FOR$CONVERT002 LITTLE_ENDIAN

  This command makes LITTLE_ENDIAN the default convert type for unit
  2.  A defined logical name for a unit overrides the /CONVERT
  compile command or OPTIONS statement qualifier and an explicit
  CONVERT= keyword on an OPEN statement.  For more information, see
  the /CONVERT qualifier.

5 - FOR$PRINT

  If defined during execution, 'FOR$PRINT' is used instead of
  'SYS$OUTPUT' as the file specification for the implicit Fortran
  logical unit used for PRINT statements and WRITE statements that
  specify * as the unit number.

6 - FOR$PROCESSES

  If defined during execution of a parallel processing application,
  this logical name controls the number of processes used.  The
  default is the number of processors available on the executing
  system.  The minimum is 1, the maximum is 32.  For more
  information, see the Compaq Fortran Performance Guide.

7 - FOR$READ

  If defined during execution, 'FOR$READ' is used instead of
  'SYS$INPUT' as the file specification for the implicit Fortran
  logical unit used for READ statements that specify * or omit the
  unit number.

8 - FOR$SPIN_WAIT

  If defined during execution of a parallel processing application,
  this logical name controls the synchronization method used.  A
  value of 0 causes busy-waiting to be used, which maximizes
  synchronization response at the expense of wasted processor cycles.
  Positive values specify the number of busy-wait cycles to execute
  before relinquishing control of the processor.  The default is
  1000.  For more information, see the Compaq Fortran Performance Guide.

9 - FOR$STALL_WAIT

  If defined during execution of a parallel processing application,
  this logical name specifies the number of spin-wait cycles (see
  FOR$SPIN_WAIT) that a parallel worker subprocess should execute
  while waiting for more work to do before becoming inactive.  A
  value of 0 prevents the process from becoming inactive.  The
  default is 10 times the number of worker subprocesses.  For more
  information, see the Compaq Fortran Performance Guide.

10 - FOR$TYPE

  If defined during execution, 'FOR$TYPE' is used instead of
  'SYS$OUTPUT' as the file specification for the implicit Fortran
  logical unit used for TYPE statements.

11 - FORnnn

  The file specification 'FORnnn', where 'nnn' is the logical unit
  number, is used as the file specification when a logical unit is
  opened and the FILE= keyword was not specified in an OPEN
  statement.  Similarly, 'FORnnn.DAT' is used as the default file
  specification unless the DEFAULTFILE= keyword was specified.
  FORnnn may be defined as a logical name, in which case it is used
  by OpenVMS RMS to specify the file to be opened.