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Chapter 4 - Exception Manager / Exception Manager Reference

Constants

Exception Kinds

The Exception Manager indicates to your exception handler the kind of exception
that has occurred by passing it an exception code. The exception kind is indicated by
a constant.

Note

Some kinds of exceptions occur only on specific types of
processors or only in specific system software versions.

enum {
   /*exception codes*/
   unknownException                    = 0,     /*unknown exception type*/
   illegalInstructionException         = 1,     /*illegal instruction*/
   trapException                       = 2,     /*unknown trap type*/
   accessException                     = 3,     /*failed memory access*/
   unmappedMemoryException             = 4,     /*memory is unmapped*/
   excludedMemoryException             = 5,     /*memory is excluded*/
   readOnlyMemoryException             = 6,     /*memory is read-only*/
   unresolvablePageFaultException      = 7,     /*unresolvable page fault*/
   privilegeViolationException         = 8,     /*privilege violation*/
   traceException                      = 9,     /*trace*/
   instructionBreakpointException      = 10,    /*instruction breakpoint*/
   dataBreakpointException             = 11,    /*data breakpoint*/
   integerException                    = 12,    /*unused*/
   floatingPointException              = 13,    /*floating point*/
   stackOverflowException              = 14,    /*stack overflow*/
   terminationException                = 15     /*task is being terminated*/
};

Constant descriptions

unknownException

Unknown kind of exception. This exception code is defined for completeness only; it is never actually passed to an exception handler.

illegalInstructionException

Illegal instruction exception. The processor attempted to decode an instruction that is either illegal or unimplemented.

trapException

Unknown trap type exception. The processor decoded a trap type instruction that is not used by the system software.

accessException

Memory access exception. A memory reference resulted in a page fault because the physical address is not accessible.

unmappedMemoryException

Unmapped memory exception. A memory reference was made to an address that is unmapped.

excludedMemoryException

Excluded memory exception. A memory reference was made to an excluded address.

readOnlyMemoryException

Read-only memory exception. A memory reference was made to an address that cannot be written to.

unresolvablePageFaultException

Unresolvable page fault exception. A memory reference resulted in a page fault that could not be resolved. The theError field of the memory exception record contains a status value indicating the reason for this unresolved page fault.

privilegeViolationException

Privilege violation exception. The processor decoded a privileged instruction but was not executing in the privileged mode.

traceException

Trace exception. This exception is used by debuggers to support single-step operations.

instructionBreakpointException

Instruction breakpoint exception. This exception is used by debuggers to support breakpoint operations.

dataBreakpointException

Data breakpoint exception. This exception is used by debuggers to support breakpoint operations.

integerException

Integer exception. This exception is not used by PowerPC processors.

floatingPointException

Floating-point arithmetic exception. The floating-point processor has exceptions enabled and an exception has occurred. (This exception is not used in the first version of the system software
for PowerPC processor-based Macintosh computers.)

stackOverflowException

Stack overflow exception. The stack limits have been exceeded and the stack cannot be expanded. (This exception is not used in the first version of the system software for PowerPC processor-based Macintosh computers.)

terminationException

Termination exception. The task is being terminated. (This exception is not used in the first version of the system software for PowerPC processor-based Macintosh computers.)