Subject: Re: 2292bis-02: zero-length setsockopt

From: [email-masked]
Date: Fri, 02 Nov 2001 14:03:59 +0900

>I guess I stuck that text in there based on some goal of consistency with
>the other IPV6_ options in the spec.
>
>Clearly(?) for IPv6_DSTOPTHDR it makes sense to be able to
>clear the sticky option by setting it to zero length.
>(I think this is consistent with setting IP_OPTIONS to zero length.)
>
>So what about IPV6_HOPLIMIT that is a fixed length quantity?
>Is it more important to be consistent with the other IPv6 options
>(and allow zero length as a way to clear it) or is it more
>important to make the option value always have a fixed length (meaning
>that -1 is the only way to set if to "default").
>
>I don't have a strong opinion either way.

	I don't feel the need for consistensy among 2292bis setsockopts.
	-1 should be fine for setting the default value for IPV6_HOPLIMIT
	and other integer setsockopt.

itojun
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From: JINMEI Tatuya / 神明達哉<[email-masked]>
Date: Fri, 09 Nov 2001 22:01:23 +0900

>>>>> On Fri, 02 Nov 2001 14:03:59 +0900, 
>>>>> [email-masked] said:

> 	and other integer setsockopt.

Okay, so I'd propose the following rule:

  - if we can find a "magic number" to disable an option, it should
    be used as the only way to disable the option.
    (the "magic numbers" include all-zero data for IPV6_PKTINFO).
  - otherwise, use a zero-length option to disable the option.

					JINMEI, Tatuya
					Communication Platform Lab.
					Corporate R&D Center, Toshiba Corp.
					[email-masked]
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