getsockopt with SO_ERROR: help!

[jay dubb]

   I am posting this for a friend of mine who doesn't have access
to USENET, so please respond directly to mlevin at jade.tufts.edu.

   I am having problems using getsockopt() with option SO_ERROR on a
connected TCP socket.  First of all, what is supposed to be the type
(size, format, etc.) of the destination (optval) parameter? And, how
does one interpret whatever information getsockopt() puts there when
it finds an error? Secondly, my call to getsockopt with optval
set to a char[100] array, and optlen pointing to an int which equals
100, sets errno to 22 = invalid argument, which is not on the list of
things that getsockopt can set errno to (according to the manual,
anyways). Any ideas as to what's causing this? Thanks in advance.

			Mike Levin (mlevin at jade.tufts.edu)