It's unclear starting from what version the kernel and headers were updated with sockets support(IORING_OP_ACCEPT etc). I just checked today 2020/01/22 Focal Rossa Ubuntu and the last OP is only IORING_OP_TIMEOUT (still on kernel 5.4.0-12) ;( So maybe it's a good idea to comment-update every io_uring.h OP with minimum kernel version requirement... p.s. Not every Linux user is a kernel hacker ;)
