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  MURPHY
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  Purpose : Create a worst case overlay situation

  Syntax  : MURPHY

  Default : Disabled

  The MURPHY causes the overlay manager to attempt to force any
  inadvertent overlay errors (programming errors) to manifest themselves
  during testing or debugging.

  When MURPHY is enabled, the overlay manager will only allow a single
  overlay to be in memory at any given time, allowing the developer to
  detect 'badly behaved' dependencies between overlays and correct them.

  The overlay manager also fills all unused space in the overlay pool with
  INT 3 instructions, with a far jump to an error reporting routine within
  the overlay manager being placed at the very end of the overlay area.

  When the program is run under a debugger, and an erroneous jump to an
  invalid (i.e. non-vectored) address within the overlay area occurs, the
  INT 3 instruction will cause the debugger to breakpoint at the offending
  address.

  If the program is not being executed under a debugger, the processor
  will execute all the INT 3 instructions and the far jump to the error
  routine in the overlay manager, at which point the overlay manager will
  display a message and terminate the program.

  The use of the MURPHY command may slow down the execution of the program
  significantly.



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