(LOGO.JPG) Python for OpenVMS

On OpenVMS definitions of item codes, bitmasks or constants are stored in several modules. E.g. for 'Device and Volume Information' the module name is '$DVIDEF'.

On OpenVMS, Python uses a similar construct that I call 'VMSDEF'.

On OpenVMS there exist different files for each language - e.g. DVIDEF.H or DVIDEF.PAS (Caution! some compilers store these files in a text library, now!).

My first release of Python for OpenVMS (released on 16-FEB-1997) did store item codes (and some more information that is not available in a native xxxDEF module of OpenVMS) in a number of '.C' source files building huge arrays.

This data, with some more information, has been moved into a number of text files with names like VMSDEF_$DVIDEF.DAT. The procedure VMSDEF2MAR.COM translates the DAT file to the file VMSDEF_$DVIDEF.MAR which is then run through the macro assembler by using the following command:

    $ @PYTHON_VMS:BLDRUN VMS_MACRO VMSDEF_$DVIDEF.MAR
The resulting object file (VMSDEF_$DVIDEF.OBJ) is put into the object library in [.VMS.O_architecture]VMS_MACRO.OLB. ('architecture' is either 'ALPHA' or 'VAX').

Look in the table of contents under 'Notes about implementation details' to see a sketch of the 'VMSDEF data structures'


Format:

    $ @VMSDEF2MAR inputfile
Arguments:
inputfile
Text file that contains the VMSDEF information. The output file is stored in the same directory with the same name - except that the file type is '.MAR'.
Example:
    $ @VMSDEF2MAR VMSDEF_$DVIDEF.DAT
    $ directory VMSDEF_$DVIDEF.*;

    Directory DKA100:[PYTHON.PYTHON-1_5.VMS]

    VMSDEF_$DVIDEF.DAT;1        VMSDEF_$DVIDEF.MAR;1

    Total of 2 files.

(go to: table of contents, Tools in TOC, index)

03-FEB-2000 ZE.