[libc-commits] [libc] [libc] implement `sys/uio/readv` (PR #124718)

[Nick Desaulniers via libc-commits]

https://github.com/nickdesaulniers approved this pull request.

Thanks for the patch. Some additional includes should polish this up.  We should probably define IOV_MAX in libc/include/llvm-libc-macros/limits-macros.h, too in order to make these functions more useful.

https://github.com/llvm/llvm-project/pull/124718