> > In any case, I did want to mention that since 8.2 Tcl has had stacked > > channels in the core. Extensions like Trf, memchan and TLS use this > > to do compression and/or encryption on channels transparent to the > > user.
> I create a new channel type in tclcmds.c in the nsopenssl module to > allow Tcl's gets, puts and friends to work with an SSL "socket", though > I didn't use channels for the C API portion of the process. > > Are there any performance issues with stacking channels? That's a good question ... I've never actually done performance analysis on the stacked channel stuff, but it is fairly efficient. It just passes buffers from one stack to the next as they are consumed. Special purpose filters may do a better job as they can suck in large amounts of data as they operate, but I'm not sure that you'd win if you have to have extra exec overhead. What would be a good test? Jeff Hobbs The Tcl Guy Senior Developer http://www.ActiveState.com/
