.debdiffs 如何应用？

Question

路过这个错误. 如何申请.debdiff？

以下是我发现的最相关的指导：

# Apply a debdiff patch.
# - PKGNAME: Name of the package
# - DEBDIFF: Deb diff file.
# - RESPACKAGE: Resulting package of debuild

# Neccesary packages to make the deb package
sudo apt-get install build-essential fakeroot devscripts

apt-get source PKGNAME
sudo apt-get build-dep PKGNAME
cd PKGNAME-*
patch -p1 < ../DEBDIFF
debuild -uc -us
sudo dpkg -i ../RESPACKAGE

# Thanks to https://wiki.ubuntu.com/UbuntuPackagingGuide/BuildFromDebdiff

（https://snipt.net/gjulian/apply-a-debdiff-patch/）

这是我的困惑/担忧：

1. 这段代码很古老。它仍然有意义吗？
2. 哪儿是PCKGNAME？
3. fix_aliasmatch_long_uri.debdiff是个DEBDIFF？
4. 啥是RESPACKAGE？
5. apt-get@ root/？