[python-sybase] ct_connect threading issue?

Thu, 3 Apr 2003 18:30:26 -0500

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<P><FONT SIZE=3D2 FACE=3D"Arial">Hi all,</FONT>

I've been trying to use the Sybase =
module with Python 2.2.2 on Win32 (W2K to be exact) w/ Sybase 11.9.2 and =
on Solaris 2.8 64 bit on Sybase 12.5. It seems that it dies with a =
thread access violation and aborts the interpreter. I've tracked down =
the issue and it dies in

<P><FONT SIZE=3D2 FACE=3D"Arial">&nbsp;status =3D =
ct_connect(self-&gt;conn, dsn, CS_NULLTERM); on line 310 of conn.c. =
</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">It seem that this method isn't thread =
safe, from the Open Clien ref manual: </FONT>
</P>

<P><B><FONT SIZE=3D2 FACE=3D"Arial">Note</FONT></B> <FONT SIZE=3D2 =
FACE=3D"Times New Roman">If ct_connect is called in the entry funtions =
of a DLL, a deadlock</FONT>

may arise. This system =
creates OS threads and tries to synchronize them

using system utilities. This =
synchronization conflicts with the operating

<BR><FONT SIZE=3D2 FACE=3D"Times New Roman">system&#8217;s serialization =
process.</FONT>
</P>

<P><FONT SIZE=3D2 FACE=3D"Arial">Too bad it doesn't explain a work =
around :) Oddly enough, if I just use 32 bit mode on Solaris and only =
use the 32 bit 11.9.2 driver it works fine (which would make sense since =
the threading models are different).</FONT></P>

<P><FONT SIZE=3D2 FACE=3D"Arial">Any help would be greatly appriciated =
(stack traces on request for Win32, Core files on Solaris).</FONT>

<BR><FONT SIZE=3D2 FACE=3D"Arial">JP</FONT>
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