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Disassembling executable image code?

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The Question is:

I searched the FAQ for the answer, but did find one.  Do you know if there are
 any utilities (VMS or third party) that will convert a OpenVMS image back to
 its original source code or something close?

The Answer is :

  Reversing the process of assembly and particularly of compliation is
  exeedingly difficult; the creation of an image is effectively a one-way
  operation given the typical code optimization, function-inlining, and
  instruction resequencing that occurs when the image is built.  Not to
  mention that constructs such as comments and symbolic variable names
  are stripped off.
  It is possible to revert executable code back to the particular platform
  native instruction set -- Macro32 for OpenVMS VAX and Macro64 for OpenVMS
  Alpha -- via a class of tool known as a disassembler.
  The OpenVMS Wizard is aware of disassemblers that have been available for
  OpenVMS VAX, but has not particularly researched the availability of
  disassemblers for OpenVMS Alpha.
  You can use the OpenVMS debugger to display decoded instructions (for
  user-mode code), as well.
  Unable to locate the source code, eh?

answer written or last revised on ( 7-DEC-2000 )

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