System.NullReferenceException using C#

Question

Hi,
I'm trying to write a client application using C# and .Net Framework 2 with Tuxedo 11gR1 and Microsoft Visual Studio 2008. I don't have access to the server but I know the WSNADDR, services names and input/output FML buffers. I also know there is an older version of Tuxedo in the server because a I have to use "WSINTOPPRE71=yes". The question is I can get results from some services, but with others all I've got is an Exception:
System.NullReferenceException
at Bea.Tuxedo.ATMI.AppContext.WrapRawBuffer(TypedBufer& tb, IntPtr buff, Int64 datalen, Int64 flags)
at Bea.Tuxedo.ATMI.AppContext.tpcall(String svc, TypedBuffer idata, TypedBuffer& odata, Int64 flags).
I can create the application context using ac = AppContext.tpinit(tpinfo), and indicating ctlname, usrname and password in tpinfo, but ac.tpcall throws this exception. If I use tpacall, the exception is thrown with tpgetrply.
Any idea?
Thanks.

Answer 1

Hi again.
I've been using .NET Reflector to see where the exception is thrown. The question is tpcall calls the function
private void WrapRawBuffer(ref TypedBuffer tb, IntPtr buff, long datalen, long flags)
and this calls
internal static bool GetTypedBufferInfo(IntPtr buffer, out long size, out string type, out string stype, int flags)
I was using tpcall with no flags (TPNOFLAGS) and this was causing the execution of the next fragment of code:
if (!(tb.Type.Equals(str) && tb.Subtype.Equals(str2)))
When the service didn't find any record, tb.Subtype was a zero length string, but str2 was null, so this throws a NullReferenceException.
Although I suppose this is not the best solution, I'm using now the value 257 for flags, ant it's working.
Maybe a bug in libwscdnet.dll version 0.9.1087.4?