Nautilus 7z压缩

Question

我知道在Ubuntu18.04上默认情况下没有安装p7zip包。尽管如此，Nautilus仍然能够创建7z档案。这怎麽可能？

Answer 1

Nautilus改变了档案压缩的机制。

ldd $(which nautilus)可执行文件的动态库列表证实了这一点。以下是最重要的一行：

$ ldd /usr/bin/nautilus
...
    libarchive.so.13 => /usr/lib/x86_64-linux-gnu/libarchive.so.13
...

它的包裹叫什么名字？

$ dpkg -S /usr/lib/x86_64-linux-gnu/libarchive.so.13
libarchive13:amd64: /usr/lib/x86_64-linux-gnu/libarchive.so.13

这个包(libarchive13)提供了什么功能？

$ apt-cache show libarchive13
Package: libarchive13
...
Description-en: Multi-format archive and compression library (shared library)
Archive formats supported are:
 .
    * tar (read and write, including GNU extensions)
...
    * zip (read only, with some limitations, uses zlib)
...
    * 7zip (read and write, with some limitations)

此外，作为进一步的证明--如果我们试图删除这个包，它将从GNOME中删除许多核心应用程序(Nautilus、further、Evince、GNOME控制中心等)：

$ sudo apt-get purge libarchive13 --simulate
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following packages will be REMOVED:
  evince* file-roller* fwupd* gir1.2-rb-3.0* gir1.2-totem-1.0* 
  gir1.2-totemplparser-1.0* gnome-control-center* gnome-software*
  gnome-software-plugin-snap* grilo-plugins-0.3-base* gvfs-backends* 
  libappstream-glib8* libarchive13* libevdocument3-4* libevview3-3*
  libgnome-autoar-0-0* libgrilo-0.3-0* libgxps2* librhythmbox-core10* 
  libtotem-plparser18* libtotem0* nautilus* rhythmbox*
  rhythmbox-plugin-alternative-toolbar* rhythmbox-plugins* totem* 
  totem-plugins* ubuntu-desktop* ubuntu-software*
0 upgraded, 0 newly installed, 29 to remove and 53 not upgraded.

所以答案是:Nautilus3.26在Ubuntu18.04LTS中不使用p7zip，它使用来自libarchive13包的函数。