I'm currently using the busybox from a CM12 repository, it's not the latest, but it is bionic aware (which means it uses Android's way of things to do instead of the linux way of things to do).
'The latest version' can mean many things, because there are a multitude of versions around. I'd like to know where to find the sources for that 'latest version' when/if it's adapted for use with Android/Bionic. (to see if it is, use that busybox to ping any host online, if it's not capable of producing an IP from a host and is unable to ping a straight IP, it's built with Libgc (which is linux' main core).
Good stuff, nice to know
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I am actually working on a solution for this, but I wanted to clear out any remaining issues before I did, otherwise it would get very confusing, very fast and possibly spiral out of control down a pit of snakes I wouldn't be able to pull it up from...
The change is to move my busybox to the .XZDualRecovery folder, creating an operating environment there instead of relying on system/bin and system/xbin. This will mean quite a big change, so I hope to do it soon, but also hope to avoid any big issues.