sybtcl/freetds hangs on sybclose/dbcancel -- what can I do?

Mikhail Teterin · *nix forums addict Joined: 23 Mar 2002 Posts: 56

Hello!

Because Sybase foolishly would not open-source the client-library, I am
forced to use FreeTDS.

When my Tcl-script (using Sybtcl) detects the remote server's misbehaviour
(such as extreme slowness), it tries to close the connection and move on.

Sometimes this hangs, however. Here is the stack:

#0 0x00000008009f487c in select () from /lib/libc.so.6
#1 0x0000000800d9a18b in tdsdump_open () from /opt/lib/libsybdb.so.5
#2 0x0000000800d9a355 in tdsdump_open () from /opt/lib/libsybdb.so.5
#3 0x0000000800d89cb3 in tdsdump_open () from /opt/lib/libsybdb.so.5
#4 0x0000000800d8681f in stat_xact () from /opt/lib/libsybdb.so.5
#5 0x0000000800d87a71 in stat_xact () from /opt/lib/libsybdb.so.5
#6 0x0000000800d738c4 in dbcancel () from /opt/lib/libsybdb.so.5
#7 0x0000000800c5e543 in Sybtcl_Close (clientData=0x0, interp=0x505400,
objc=2, objv=0x513008)
at /usr/ports/databases/sybtcl/work/sybtcl-3.0rc2/generic/sybtcl.c:4121
#8 0x000000080065d5d5 in TclEvalObjvInternal (interp=0x505400, objc=2,
objv=0x513008, command=0x0, length=0, flags=0)
at ./../generic/tclBasic.c:3088
#9 0x0000000800690283 in TclExecuteByteCode (interp=0x505400,
codePtr=0x6de000) at ./../generic/tclExecute.c:1417
[...]

How can I detect such situation from Tcl and force sybtcl to abandon the
attempt to "say goodbye"?

Thanks!

-mi

Michael Peppler · *nix forums Guru Wannabe Joined: 15 May 2005 Posts: 112

On Wed, 14 Jun 2006 23:18:28 -0400, Mikhail Teterin wrote:

Mikhail Teterin · *nix forums addict Joined: 23 Mar 2002 Posts: 56

Google