Re: question on select: How big can the empty buffer space be before select returns ready-to-write?

Chris Wright (chris@wirex.com)
Mon, 10 Dec 2001 13:46:26 -0800


* Christopher Friesen (cfriesen@nortelnetworks.com) wrote:
> Chris Wright wrote:
> >
> > * Ben Greear (greearb@candelatech.com) wrote:
> > > For instance, it appears that select will return that a socket is
> > > writable when there is, say 8k of buffer space in it. However, if
> > > I'm sending 32k UDP packets, this still causes me to drop packets
> > > due to a lack of resources...
> >
> > udp has a fixed 8k max payload. did you try breaking up your packets?
>
> Are you sure about that? UDP has a 16-bit field for the length. Thus the
> standard technically allows for packet sizes (including header) of up to 2^16
> (roughly 65K) bytes.

no, you are absolutely right, it's 16 bits. sorry for spewing
misinformation.

cheers,
-chris
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