The most frequent request is to move the TclX signal handling commands into Tcl. This page is to formalise that desire, leading to a TIP. There is some discussion/question as to the wisdom of doing this in TclX Future.
The TclX commands falling into this category are:
LV Why is execl and fork in this list? They really are not related to signaling - more to posix.
It should also be pointed out that signals are actually talked about in the C standard, so really they are not strictly bound to POSIX. --Setok