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Hey everyone,

I have a question out of complete curiosity

I have seen alot of code use an infinity loop to "halt" execution. My question is "why"?

i.e., why not use HLT or a combination of CLI and HLT?

Is it just personal preference?

Using CLI in combination with HLT will completely halt the system, and is more efficient then a jmp $ instruction.

Using HLT alone halts the processor, but still allows execution of interrupts (Which can restart the processor, when needed)

Is there any specific reason?

Just curious,

Thanks

For some reason I just feel that a hlt is not as final as jmp $. But I usually use in my code.

I uses the same as frank, if not it will run at near 100% in single-tasking OS.
You can find lots of case of why do coders do this and that, eg: in Pmode why do coders do pusha and popa, instead of pushad or popad ?.

even CLI + HLT can still be restarted (with an NMI, that is) An infinite loop can't be passed over in such a fashion. The reason to use a halt-loop construct is to conserve energy.

If you really want to lock up the computer, try to trigger the F00F bug

Combuster wrote:even CLI + HLT can still be restarted (with an NMI, that is) An infinite loop can't be passed over in such a fashion. The reason to use a halt-loop construct is to conserve energy.

If you really want to lock up the computer, try to trigger the F00F bug

lol--I just might do that!

You are correct about the NMIs though--I did not think of that.