Making IPC_PRIVATE available to userland

Hi all, the POSIX standard doesn't mandate that IPC_PRIVATE has any particular value; in practise it is often (maybe always) zero, but I think the constant is important enough to deserve its own PHP userland constant. It would be useful for shmop_open(), shm_attach() and sem_get(), but these three functions belong to three different extensions (shmop, sysvshm, sysvsem), so it is not clear where to define the constant, and how to name it. My first thought was to define PHP_IPC_PRIVATE in main.c, but Nikita had reasonable objections to expose the constant from core. I came up with a somewhat doubtful alternative[1]; a maybe even worse alternative would be to define three separate constants. Has anybody an idea how to solve that? Of course, you could also comment on <https://github.com/php/php-src/pull/5527> directly. [1] <https://github.com/php/php-src/pull/5527/commits/a33d2f3921e53810873e6cbb7856234e24520ab8> Thanks, Christoph