有时使用yum install时会出现如下错误，导致软件无法安装。
Loaded plugins: fastestmirror
Cleaning repos: base epel extras mysql-connectors-community mysql-tools-community
: mysql56-community updates
14 metadata files removed
0 sqlite files removed
0 metadata files removed
Loaded plugins: fastestmirror
base | 3.6 kB 00:00:00
epel | 4.7 kB 00:00:00
extras | 3.4 kB 00:00:00
mysql-connectors-community | 2.5 kB 00:00:00
mysql-tools-community | 2.5 kB 00:00:00
mysql56-community | 2.5 kB 00:00:00
updates | 3.4 kB 00:00:00
File "/usr/libexec/urlgrabber-ext-down", line 28
except OSError, e:
^
SyntaxError: invalid syntax
File "/usr/libexec/urlgrabber-ext-down", line 28
except OSError, e:
^
SyntaxError: invalid syntax
File "/usr/libexec/urlgrabber-ext-down", line 28
except OSError, e:
^
SyntaxError: invalid syntax
File "/usr/libexec/urlgrabber-ext-down", line 28
except OSError, e:
^
SyntaxError: invalid syntax
File "/usr/libexec/urlgrabber-ext-down", line 28
except OSError, e:
^
SyntaxError: invalid syntaxExiting on user cancel
这个yum的一个bug，解决的办法是修改/usr/lib/python2.7/site-packages/urlgrabber/grabber.py文件。
elif errcode == 42:
# this is probably wrong but ultimately this is what happens
# we have a legit http code and a pycurl ‘writer failed‘ code
# which almost always means something aborted it from outside
# since we cannot know what it is -I‘m banking on it being
# a ctrl-c. XXXX - if there‘s a way of going back two raises to
# figure out what aborted the pycurl process FIXME
raise KeyboardInterrupt
修改后：
#elif errcode == 42:
# this is probably wrong but ultimately this is what happens
# we have a legit http code and a pycurl ‘writer failed‘ code
# which almost always means something aborted it from outside
# since we cannot know what it is -I‘m banking on it being
# a ctrl-c. XXXX - if there‘s a way of going back two raises to
# figure out what aborted the pycurl process FIXME
#raise KeyboardInterrupt
然后切换到root用户，执行以下命令：
yum clean metadata
yum clean all
yum upgrade
执行完后，重新执行安装命令，大多数人应该都解决了，但是博主运气较差，并没有解决。
后来各种鼓捣，又修改了/usr/bin/yum文件，将第一行修改为如下内容：
#!/usr/bin/python2
但是新问题又来了：
[[email protected] conf]# yum -y install php
File "/usr/bin/yum", line 30
except KeyboardInterrupt, e:
^
SyntaxError: invalid syntax
解决方法就是，修改/usr/libexec/urlgrabber-ext-down文件，将第一行修改为如下内容：
#! /usr/bin/python2
至此，终于可以愉快的安装软件了。
原文地址：https://www.cnblogs.com/feilstar/p/10284890.html