On 25.12.2006, at 11:22, Zoran Vasiljevic wrote:
It seems that stdin/stdout/stderr channels are not properly handled on thread exit (not detached from the interp).
Well, this is going to be tough... The scenario is simple: Tcl has channel wrappers for stdin, stdout and stderr channels. On a virgin interp and new thread the first call to some channel handling command will try to initialize per-interp channel table. This in turn will try to get all those three std channels initialized. On interp teardown, those channels are not removed (Tcl_Close'd) as this may result in closing of the underlying descriptor for the whole process! Hence those three chans are never closed! Therefore, you leak 3 channels every time you exit a thread that uses Tcl and some of the channel commands. In our case, we ALWAYS leak 3 channels. As the part of the interp deallocation, we always try to close non-stderr channels and thus invoke [file channels] that in turn lazy-initialize std channels. Shortly: Tcl always creates 3 channels arround stdin/stderr/stdout descriptors for a new thread/interp. Tcl never closes those channels on thread exit, as this will close the underlying descriptor and have large side-effect on whole process. The only chance is to artificially plumb the channel structure and remove (or redefine) closeproc elements for std channels. This is a GREAT mess and I will have to wait for Andreas (Kupries) to come back from vacation so we can jointly attack that stupid bug.
