haiku/docs/develop/net/HowTo-Synchronize_with_NetBSD.md

How to Merge Patches from NetBSD Trunk
============================================
Using the NetBSD CVS is a pain, so instead, the preferred thing to do is to use
[the official Git mirror](https://github.com/NetBSD/src). The code here is
in the tree at a few places:`inet` is at `lib/libc/inet`, irs is scattered
across the tree, and `resolv` is at `lib/libc/resolv`.

The preferable way to merge is to take the last commit merged from IIJ's mirror
(can be found in the merging commit in Haiku, if the merger has done their work
properly) and check all commits since then to see if they apply or not (some
apply to documentation we don't have, etc.) Cherry-pick the ones that do, and
download them as git-format-patch patches (by adding `.patch` onto the end of the
commit URL).

To convert the patches to have the correct paths to the resolv/inet/etc. code, use
`sed`:
```
sed s%lib/libc/resolv%src/kits/network/netresolv/resolv%g -i *.patch
```
(You'll need to use similar commands for the `inet` and `irs` code.)

Then apply the patches using `git apply --reject file.patch`. Git will spew a lot of
errors about files in the patch that aren't in the tree, and then it will warn that
some hunks are being rejected. Review the rejected hunks **VERY CAREFULLY**, as
some code in Haiku's NetResolv is not in NetBSD's and vice versa, and so some patches
may not apply cleanly because of that. You might have to resort to merging those
hunks by hand, if they apply at all to Haiku's code.

Commit the changes all at once, but list all the commits merged from NetBSD
in the commit message (see previous merges for the style to follow).