显示数据源中包的统计信息

6.4.1 显示数据源中包的统计信息
"apt-cache stats"命令用于显示当前系统所使用的Debian数据源的统计信息。

debian:~# apt-cache stats
Total package names : 24148 (966k)
Normal packages: 18698
Pure virtual packages: 301
Single virtual packages: 1223
Mixed virtual packages: 196
Missing: 3730
Total distinct versions: 19709 (946k)
Total dependencies: 124470 (3485k)
Total ver/file relations: 20598 (330k)
Total Provides mappings: 4163 (83.3k)
Total globbed strings: 95 (1061)
Total dependency version space: 484k
Total slack space: 125k
Total space accounted for: 5936k

6.4.2 按关键字查找软件包
"apt-cache search"命令可以按关键字查找相关的软件包，通常用于查询的关键字会使用软件包的名字或包名字的一部分。"apt-cache search"命令查询的结果将显示相关软件包和软件包的简短描述。

debian:~# apt-cache search mkinitrd
bootcd-mkinitrd - bootcd extension to create an initrd-image usable for bootcd
mkinitrd-cd - Creates an initrd image for booting from a live CD-ROM or USB device
yaird - Yet Another mkInitRD

6.4.3 显示软件包的详细信息
"apt-cache show"命令显示指定软件包的详细信息。

debian:~# apt-cache show bootcd-mkinitrd
Package: bootcd-mkinitrd
Priority: extra
Section: utils
Installed-Size: 80
Maintainer: Bernd Schumacher <[email protected]>
Architecture: all
Source: bootcd
Version: 2.53
Depends: initrd-tools, discover | discover1, busybox | busybox-static | busybox-cvs | busybox-cvs-static, bootcd (>= 2.50)
Filename: pool/main/b/bootcd/bootcd-mkinitrd_2.53_all.deb
Size: 16046
MD5sum: ea632fbe7e3584e29fe52510a3dbf3bc
Description: bootcd extension to create an initrd-image usable for bootcd
With bootcd you can copy your system to cd, run it from cd without need for
disks and restore your system on disk from bootcd.
This Package should be installed on a system you want to copy to cd, if the
kernel uses initrd (as all prebuild debian 2.4 and 2.6 kernels do).
With the command bootcdmkinitrd your initrd.img can be changed to use
discover and to automatically detect the cdrom the bios used to boot.
Tag: admin::boot, admin::filesystem, hardware::storage, hardware::storage:cd, role::sw:plugin

6.4.4 查询软件包的依赖关系
了解某个软件包依赖于其他哪些软件包是，使用"apt-cache depends"

bootcd-mkinitrd
Depends: initrd-tools
|Depends: discover
Depends: discover1
|Depends: busybox
|Depends: busybox-static
|Depends: <busybox-cvs>
Depends: <busybox-cvs-static>
Depends: bootcd

6.4.5 查询软件包的反向依赖关系
"apt-cache rdepend" 命令用于查询指定软件包的反向依赖关系，即那些其他的软件包需要依赖指定的软件包作为安装和运行的必须条件。

debian:~# apt-cache rdepends bootcd-mkinitrd
bootcd-mkinitrd
Reverse Depends:
bootcd