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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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