如何从测试中提取包/测试的依赖项

Question

尝试安装一个更新版本的libav工具，从测试到我的debian稳定安装。我在sources.list中进行了测试，我的首选项如下所示：

Package: *
Pin: release a=stable
Pin-Priority: 995

Package: *
Pin: release a=testing
Pin-Priority: 101

如果我正确理解维基，apt-get install pkg/testing将从testing安装pkg，但不会为了满足依赖关系而进行升级，而apt-get -t testing install pkg/testing应该这样做。然而..。

apt-get -t testing install libav-tools的输出：

Reading package lists... Done
Building dependency tree       
Reading state information... Done
libav-tools is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 12 not upgraded.

apt-get install libav-tools/testing的输出：

Selected version '6:9.10-2' (Debian:testing [i386]) for 'libav-tools'
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 libav-tools : Depends: libavcodec54 (>= 6:9.1-1) but it is not going to be installed or
                        libavcodec-extra-54 (>= 6:9.10) but it is not going to be installed
              ... *truncated*
E: Unable to correct problems, you have held broken packages.

apt-get -t testing install libav-tools/testing的输出是相同的。

因此，似乎-t开关本身并没有找到最新的软件包版本，而/testing却在脱离deps。有人能告诉我这是用户错误还是错误吗？

Answer 1

丹，在运行稳定的时候改变稳定的优先级通常是一个大的不-不，afaik，而且没有真正的意义。您想要用于测试/不稳定的典型类型的数字是Pin Priority 50，您不想触及稳定的数字。

我查看了您引用的Wiki页面(至少从一开始阅读man apt_preferences会更好)，而且没有人建议将优先级数字设置为稳定。或者更广泛地说，您正在运行的系统。

有了这些值，-t testing和/testing就会像您预期的那样运行。无论如何，总的来说，-t testing并不是一个好主意(除非你真的知道自己在做什么)。

如果您想对正在发生的事情进行更详细的分析，我认为/testing所发生的情况是包参数(S)的优先级暂时增加(在该命令中)，可能是500。对于-t testing，它会将测试中的所有内容都处理掉。但是，如果您已经将稳定的优先级提高到500以上，这将不会像预期的那样起作用。可以对其进行更详细的分析--可能会询问程序包在命令中有哪些优先级，但我不知道如何做到这一点。

运行一个快速测试-颠簸稳定到995 (我的测试和不稳定保持在50)支持上述分析。-t testing slrn 995拒绝做任何事情。它的正常值为500，它试图升级232个软件包。

这是995箱的输出。这500个箱子太长了，不包括在这里。

apt-get install -t unstable slrn
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 slrn : Depends: libc6 (>= 2.15) but 2.13-38+deb7u1 is to be installed
E: Unable to correct problems, you have held broken packages.