skeleton: add /dev/fd, /dev/std{in, out, err} symlinks for static /dev on readonly rootfs

2018-05-01T19:53:45+00:00

Some applications, e.g. bashs process subsitution feature, rely on the convention of `/dev/fd` being a symbolic link to `/proc/self/fd`. When a static /dev is used on a readonly rootfs then the runtime ln invocations in the inittab will fail, so we need to add the symlinks at build time. Makedevs doesn't support creating symlinks, so instead add the symlinks to the default skeleton. For non-static /dev setups, the kernel will mount devtmpfs which shadows the /dev of the rootfs, but then the runtime ln invocations in inittab will create the symlinks. Signed-off-by: Peter Korsgaard

buildroot/system/skeleton/dev/stdout, branch 2019.02-op-build

skeleton: add /dev/fd, /dev/std{in, out, err} symlinks for static /dev on readonly rootfs