>>GetLastError will
>>> give much more details than errno.
>>
>>How much more, really?  That mapping table gave me the impression that
>>the win32 error codes aren't all that much more detailed than errno...
>
>The mapping table is not complete. My winerror.h from the SDK
>lists 2209
>error codes, whereas errno.h lists 42...
>
>I still don't think we'll get that much more stuff. Right now,
>the Win32
>code paths that actually use the more advanced functions already write
>out the error number in case something happens. We can keep doing that
>for the other paths (ereport the error *number* when the mapping does
>not have a match). The map to errno will catch almost all cases, I
>think. And in the corner cases we can do with just the number, and use
>"net helpmsg" to get the actual message when checking...

Here's an attempt on this. new file goes in backend/port/win32.

Magnus Hagander