On Mon, 12 Nov 2018, Daniel Colascione wrote: > The two features *are* unrelated. The design I've proposed works > equally well for synchronous and asynchronous signals, and limiting it Whatever the design, I see no obvious reason why a kernel-provided library, with all the problems that entails, should need to be involved, rather than putting new APIs either in libc or in a completely separate libsignal for libraries wanting to use such a system for cooperative signal use. (I can imagine *other* parts of the toolchain being involved, if e.g. you want to have a good way of checking "is the address of the instruction causing this signal in this library?" that works with static as well as dynamic linking - for dynamic linking, I expect something could be done using libc_nonshared and __dso_handle to identify code in the library calling some registering function. And indeed there might also be new kernel interfaces that help improve signal handling.) In the absence of consensus for adding such a new API for signals to glibc, it's unlikely one would get consensus for glibc to depend on some other library providing such an API either. But you can always write a library (which I think would most naturally be a completely separate libsignal, not part of the kernel source tree) and seek to persuade libraries they should be using it rather than interfering with global state by registering normal signal handlers directly. -- Joseph S. Myers joseph@xxxxxxxxxxxxxxxx
