FreeTDS Development Group

[Craig Spannring <cts AT internetcds.com>]

ark AT eltex.ru writes:
 > -----BEGIN PGP SIGNED MESSAGE-----
 > 
 > nuqneH,
 > 
 > Ok, i (at least i think so) solved my OOB problem.
 > Short summary - how does OOB work in TDS 4:
 > Cancel message has no data, just header:
 > 
 > 0x06 "Cancel" message
 > 0x01 the last and only fragment
 > 0x00 \ message size is 8, nbo
 > 0x08 /
 > 0x00 \ channel is 0
 > 0x00 /
 > 0x01 pktnum is 1
 > 0x00 window is 0, and _this byte_ is sent as OOB so you need
 > setsockopt(..,SO_OOBINLINE..) to read it.

You don't want to send only the last byte OOB.  The packet could get
fragmented and the OOB could conceivably be received before the rest
of the packet.  I don't think SQL Server is going to like that.

For an example of cancel handling you might want to look at
CancelController.java in the freetds_jdbc driver.


-- 
=======================================================================
 Life is short.                  | Craig Spannring 
      Bike hard, ski fast.       | cts AT internetcds.com
 --------------------------------+------------------------------------
 Any sufficiently horrible technology is indistinguishable from Perl.
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