为什么apt安装后的文件权限与dpkg -c不同？

Question

我只是好奇是什么决定了apt安装的文件的文件权限。

运行apt download transmission，然后运行dpkg -c transmission-daemon_2.94-2ubuntu3_amd64.deb，显示所有文件都属于root：

drwxr-xr-x root/root         0 2020-03-26 01:56 ./
drwxr-xr-x root/root         0 2020-03-26 01:56 ./etc/
drwxr-xr-x root/root         0 2020-03-26 01:56 ./etc/default/
-rw-r--r-- root/root       562 2019-01-02 12:50 ./etc/default/transmission-daemon
drwxr-xr-x root/root         0 2020-03-26 01:56 ./etc/init/
-rw-r--r-- root/root       654 2019-01-02 12:50 ./etc/init/transmission-daemon.conf
drwxr-xr-x root/root         0 2020-03-26 01:56 ./etc/init.d/
-rwxr-xr-x root/root      1975 2019-01-02 12:50 ./etc/init.d/transmission-daemon
drwxr-xr-x root/root         0 2020-03-26 01:56 ./etc/transmission-daemon/
-rw-r--r-- root/root       303 2019-01-02 12:50 ./etc/transmission-daemon/README.json
-rw-r--r-- root/root       523 2019-01-02 12:50 ./etc/transmission-daemon/settings.json
drwxr-xr-x root/root         0 2020-03-26 01:56 ./lib/
drwxr-xr-x root/root         0 2020-03-26 01:56 ./lib/systemd/
drwxr-xr-x root/root         0 2020-03-26 01:56 ./lib/systemd/system/
-rw-r--r-- root/root       284 2020-03-26 01:56 ./lib/systemd/system/transmission-daemon.service
drwxr-xr-x root/root         0 2020-03-26 01:56 ./usr/
drwxr-xr-x root/root         0 2020-03-26 01:56 ./usr/bin/
-rwxr-xr-x root/root    543528 2020-03-26 01:56 ./usr/bin/transmission-daemon
drwxr-xr-x root/root         0 2020-03-26 01:56 ./usr/share/
drwxr-xr-x root/root         0 2020-03-26 01:56 ./usr/share/bug/
drwxr-xr-x root/root         0 2020-03-26 01:56 ./usr/share/bug/transmission-daemon/
-rw-r--r-- root/root        95 2019-01-02 12:50 ./usr/share/bug/transmission-daemon/presubj
drwxr-xr-x root/root         0 2020-03-26 01:56 ./usr/share/doc/
drwxr-xr-x root/root         0 2020-03-26 01:56 ./usr/share/man/
drwxr-xr-x root/root         0 2020-03-26 01:56 ./usr/share/man/man1/
-rw-r--r-- root/root      1992 2020-03-26 01:56 ./usr/share/man/man1/transmission-daemon.1.gz
drwxr-xr-x root/root         0 2020-03-26 01:56 ./var/
drwxr-xr-x root/root         0 2020-03-26 01:56 ./var/lib/
drwxr-xr-x root/root         0 2020-03-26 01:56 ./var/lib/transmission-daemon/
drwxr-xr-x root/root         0 2020-03-26 01:56 ./var/lib/transmission-daemon/.config/
drwxr-xr-x root/root         0 2020-03-26 01:56 ./var/lib/transmission-daemon/.config/transmission-daemon/
drwxr-xr-x root/root         0 2020-03-26 01:56 ./var/lib/transmission-daemon/downloads/
lrwxrwxrwx root/root         0 2020-03-26 01:56 ./usr/share/doc/transmission-daemon -> transmission-common
lrwxrwxrwx root/root         0 2020-03-26 01:56 ./var/lib/transmission-daemon/.config/transmission-daemon/settings.json -> /etc/transmission-daemon/settings.json
lrwxrwxrwx root/root         0 2020-03-26 01:56 ./var/lib/transmission-daemon/info -> .config/transmission-daemon

但是，在ls -lha /etc/transmission-daemon之后运行apt install transmission-daemon向我展示了一些文件不属于root：

total 16K
drwxrwsr-x   2 root                debian-transmission 4.0K Jun 20 19:10 .
drwxr-xr-x 106 root                root                4.0K Jun 20 19:10 ..
-rw-r--r--   1 root                root                 303 Jan  2  2019 README.json
-rw-rw----   1 debian-transmission debian-transmission  523 Jan  2  2019 settings.json

Answer 1

为了查看传输守护进程使用的posi安装脚本，请运行：

apt download transmission-daemon

传输-守护进程3.00-2 ubuntu2_amd64.deb将被下载。

(版本号可能略有不同)

• 现在，使用您最喜欢的归档提取器或右键单击deb文件，然后使用您的文件管理器在这里解压.deb包。
• 在解压缩的目录中，您应该看到："control.tar.zst“、"data.tar.zst”、“debian-二进制”。
• 现在提取control.tar.zst
• 你应该看看剧本。(我们对preinst &postinst感兴趣)
• 可以随意查看preinst脚本。(只有几行)
• 完成之后，打开postinst脚本，然后查看chperms()函数及其使用情况。

探索快乐！