OS & Hardware
Which is the usual distinction between interrupts and exceptions?
- AInterrupts are raised only by software, while exceptions are raised only by hardware circuits
- BInterrupts come from external causes such as devices; exceptions result from executing an instruction
- CInterrupts can never return to the interrupted work, while exceptions always can
Show answer and explanation
Answer: B. Interrupts come from external causes such as devices; exceptions result from executing an instruction
Interrupts are caused by external events unrelated to the instruction being executed, such as I/O completion or a timer, and can arrive at any time (asynchronous). Exceptions result from executing a particular instruction, such as division by zero, an illegal instruction, a page fault or a system-call instruction (synchronous). Both are usually handled and then return to the interrupted work, so returnability is not the distinction.
- A. Dividing them by software versus hardware source is incorrect.
- B. Correct. Asynchronous external interrupts versus synchronous instruction-caused exceptions.
- C. Both usually return afterward; returnability is not the distinction.