September 6th, 2006

fedora 蓝色小药丸

yum 的新功能

Panu Matilainen
PMATILAI laiskiainen.org致 Development

> Unable to read version lock configuration: [Errno 5] OSError: [Errno
> 2] No such file or directory: '/etc/yum/pluginconf.d/versionlock.list'

...but this is by design - if the versionlock plugin is enabled it will
refuse to do anything at all unless a versionlock list can be found. The
rationale is that if you care enough about package versions to use
versionlock plugin, you don't want a config file gone missing (or
unreachable due to network break etc) mean that the system can be
updated to any available package versions. So it needs to stop.

The fix is to either 'rpm -e yum-versionlock' if you don't use it or to
provide the missing config file.

- Panu -

Panu Matilainen
PMATILAI 致 Development

On Tue, 2006-09-05 at 16:14 -0400, seth vidal wrote:
> On Tue, 2006-09-05 at 23:03 +0300, Panu Matilainen wrote:
> > Yum CVS just gained the ability to downgrade packages, with a little
> > help from yet another plugin. Means you can downgrade to manually
> > specified version of a package with --allow-downgrade assuming you have
> > the plugin installed.
> >
> > Apt-rpm supports crack like 'apt-get install "foo<1.2"' but hell is
> > going to freeze over a couple of times before Seth will accept things
> > like that in Yum :) OTOH it would probably be possible to write a plugin
> > to "revert to previous version" now, implementation is left as an
> > excercise for the reader though...
> yum already supports >=< options - it was part of the
> provides-based-installs.

So the hell frozen over already god knows how many times :) Didn't
remember that, possibly because it doesn't actually downgrade the
package if already installed to meet the requirement. Anyway, that seems
to work as well with --allow-downgrade now.

- Panu -

又,那个 yum 的插件貌似很多很多吗,我的机器上只装了四五个
  • Current Music
    foobar2000 v0.9.3 beta 2
  • Tags
fedora 蓝色小药丸

(no subject)


CMS, ICC, CMM, Device Integration

但是 CMS 这种东西.. Linux 下面,可能吗。

看的是 DesktopColorPhotoPrintingExample.pdf 文件。就 Printing in Color Communication 而言,那句 “Predict color: create device spedific color, and device simuation” 简直是充满了想象力,让人觉得 Apple 的 ColorSync 太完美了 :p

另一句话是 “ICC Profiles: Describe how to transform colors between device color space and interchange space (PCS, Profile Connection Space)”,然后下一页说,“CMMs: Provide the mathematical engine to perform color transformations”

..假设要在目的设备中使用源设备中不存在的颜色,以得到更好的表现力,岂不是会失真了(比如说,和屏幕不一致)?然后按照 Color Communication,在输出之前就可以根据 ICC Profile,再次转换回屏幕显示,前后两张屏幕图片会不会差别很大呢。不过那才是真正的打印预览,我想。

颜色单位相同的时候,比如都是 RGB,还需要颜色转换吗?
PCS 有多少种?