linux fontconfig字体报错问题

系统在运行一些程序时出现了fontconfig error的问题，经排查在python的matplot语句运行时会报这类错，虽然对结果没有什么影响，但这一堆报错不是强迫症看着都难受
于此同时，发现启动gedit时也会报此类错误
网上查找该类错误，发现这是一个悬而未决的问题，有帖子讨论过此问题，但并没有找到解决方案。

wangyihu2020@wangyihu2020-LEGION-REN7000K-26IOB:~$ gedit test
Fontconfig warning: "/etc/fonts/fonts.conf", line 5: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/fonts.conf", line 6: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/fonts.conf", line 6: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/fonts.conf", line 6: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/fonts.conf", line 7: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/fonts.conf", line 7: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/fonts.conf", line 9: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/10-hinting-slight.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/10-hinting-slight.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/10-hinting-slight.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/10-hinting-slight.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/10-hinting-slight.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/10-hinting-slight.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/10-hinting-slight.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/20-unhint-small-vera.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/25-unhint-nonlatin.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/25-unhint-nonlatin.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/25-unhint-nonlatin.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/25-unhint-nonlatin.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/25-unhint-nonlatin.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/25-unhint-nonlatin.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/25-unhint-nonlatin.conf", line 8: unknown element "description"
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 4: unknown element "its:rules"
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 5: unknown element "its:translateRule"
Fontconfig error: "/etc/fonts/conf.d/30-metric-aliases.conf", line 5: invalid attribute 'translate'
Fontconfig error: "/etc/fonts/conf.d/30-metric-aliases.conf", line 5: invalid attribute 'selector'
Fontconfig error: "/etc/fonts/conf.d/30-metric-aliases.conf", line 6: invalid attribute 'xmlns:its'
Fontconfig error: "/etc/fonts/conf.d/30-metric-aliases.conf", line 6: invalid attribute 'version'
Fontconfig warning: "/etc/fonts/conf.d/30-metric-aliases.conf", line 8: unknown element "description"
.....

从错误信息看，应该是调包时候不认识一些固定的代码格式，那么问题可能出在版本不匹配上
故猜想gedit及一些代码运行环境中调的fontconfig包与系统fontconfig包版本不一致

通过在根目录搜索libfontconfig包，找到了libfontconfig.so.1, libfontconfig.so.1.10.1, libfontconfig.so.1.12.1等文件，而且数目很多，经过观察他们分属于不同的软件环境中，即许多软件在调用时会调用自己的libfontconfig库

第一个想法是用.so.1.12.0替换.so.10.1，但试了好几个名为.so.12.0的文件，都有不同的报错。

突然想起来fontconfig库每个ubuntu系统都是有的，但只有本人报这类错，于是乎比较了同事主机上的该库文件与本人主机上的该库，发现文件有细微不同
如下：

图上看，确实是本人主机上的文件多了几行，而这几行正是报错信息提示的一些tag，仔细看了下这句里有个网址，点进去是w3c官网的ITS标准，原来本人主机此库的代码多包含的几行为ITS版本信息，属于开发者添加的描述信息，而这些描述信息不能被旧的libfontconfig.so.1.10.1正确识别，故报错。但由于描述信息不影响正常信息，所以运行结果除了一堆报错外没有其它问题。
故解决方案很简单，同事电脑上的库文件是没有问题的，把/etc/fonts/用upan拷过来替换就完事了hhh