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

  CONVERT = fm

  fm  Is a character expression with one of the following
      options:

     'LITTLE_ENDIAN'- Little endian integer data of the
                      appropriate size (INTEGER*1, INTEGER*2,
                      or INTEGER*4) and IEEE floating-point
                      data of the appropriate size and
                      type (REAL*4, REAL*8, COMPLEX*8, COMPLEX*16).
                      INTEGER*1 data is the same for little endian
                      and big endian.

     'BIG_ENDIAN' -   Big endian integer data of the appropriate
                      size (INTEGER*1, INTEGER*2, or INTEGER*4)
                      and IEEE floating-point data of the
                      appropriate size and type (REAL*4, REAL*8,
                      COMPLEX*8, COMPLEX*16).  INTEGER*1 data is
                      the same for little endian and big endian.

     'CRAY' -         Big endian integer data of the appropriate
                      size (INTEGER*1, INTEGER*2, or INTEGER*4)
                      and CRAY floating-point data of size REAL*8
                      or COMPLEX*16.

     'IBM' -          Big endian integer data of the appropriate
                      size (INTEGER*1, INTEGER*2, or INTEGER*4)
                      and IBM System\370 floating-point data of
                      size REAL*4 or COMPLEX*8 (IBM short 4)
                      and size REAL*8 or COMPLEX*16 (IBM long 8).

     'VAXD' -         Little endian integer data of the appropriate
                      size (INTEGER*1, INTEGER*2, or INTEGER*4)
                      and Compaq VAX floating-point data of
                      format F_floating for size REAL*4 or COMPLEX*8,
                      and D_floating for size REAL*8 or COMPLEX*16.

     'VAXG' -         Little endian integer data of the appropriate
                      size (INTEGER*1, INTEGER*2, or INTEGER*4)
                      and Compaq VAX floating-point data of
                      format F_floating for size REAL*4 or COMPLEX*8,
                      and G_floating for size REAL*8 or COMPLEX*16.

     'NATIVE' -       No data conversion.  This is the default.

  You can use CONVERT to specify multiple formats in a single
  program, usually one format for each specified unit number.

  When reading a non-native format, the non-native format on disk is
  converted to native format in memory.  If a converted non-native
  value is outside the range of the native data type, a run-time
  message appears.

  There are other ways to specify numeric format for unformatted
  files:  you can specify a VMS logical name or the compiler option
  CONVERT (or OPTIONS/CONVERT).  The order of precedence is VMS
  logical name, OPEN (CONVERT=), OPTIONS/CONVERT, and then compiler
  option CONVERT.  The CONVERT compiler option and OPTIONS/CONVERT
  affect all unit numbers used by the program, while logical names
  and OPEN (CONVERT=) affect specific unit numbers.

  The following source code shows how to code the OPEN statement to
  read unformatted CRAY numeric data from unit 15, which might be
  processed and possibly written in little endian format to unit 20:

     OPEN (CONVERT='CRAY', FILE='graph3.dat', FORM='UNFORMATTED',
    1     UNIT=15)
       .
       .
       .
     OPEN (FILE='graph3_native.dat', FORM='UNFORMATTED', UNIT=20)

  For more information on transporting data to or from an OpenVMS VAX
  system and on supported ranges for data types, see your user
  manual.