博客

[root@46500f7f3367 ]# yum install httpd
Loaded plugins: fastestmirror, ovl
Loading mirror speeds from cached hostfile
 * base: mirror.jdcloud.com
 * extras: ap.stykers.moe
 * updates: mirror.jdcloud.com
Resolving Dependencies
--> Running transaction check
---> Package httpd.x86_64 0:2.4.6-90.el7.centos will be installed
--> Processing Dependency: httpd-tools = 2.4.6-90.el7.centos for package: httpd-2.4.6-90.el7.centos.x86_64
--> Processing Dependency: system-logos >= 7.92.1-1 for package: httpd-2.4.6-90.el7.centos.x86_64
--> Processing Dependency: /etc/mime.types for package: httpd-2.4.6-90.el7.centos.x86_64
--> Processing Dependency: libaprutil-1.so.0()(64bit) for package: httpd-2.4.6-90.el7.centos.x86_64
--> Processing Dependency: libapr-1.so.0()(64bit) for package: httpd-2.4.6-90.el7.centos.x86_64
--> Running transaction check
---> Package apr.x86_64 0:1.4.8-5.el7 will be installed
---> Package apr-util.x86_64 0:1.5.2-6.el7 will be installed
---> Package centos-logos.noarch 0:70.0.6-3.el7.centos will be installed
---> Package httpd-tools.x86_64 0:2.4.6-90.el7.centos will be installed
---> Package mailcap.noarch 0:2.1.41-2.el7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

==============================================================================================================
 Package                    Arch                 Version                             Repository          Size
==============================================================================================================
Installing:
 httpd                      x86_64               2.4.6-90.el7.centos                 base               2.7 M
Installing for dependencies:
 apr                        x86_64               1.4.8-5.el7                         base               103 k
 apr-util                   x86_64               1.5.2-6.el7                         base                92 k
 centos-logos               noarch               70.0.6-3.el7.centos                 base                21 M
 httpd-tools                x86_64               2.4.6-90.el7.centos                 base                91 k
 mailcap                    noarch               2.1.41-2.el7                        base                31 k

Transaction Summary
==============================================================================================================
Install  1 Package (+5 Dependent packages)

Total download size: 24 M
Installed size: 31 M
Is this ok [y/d/N]: y
Downloading packages:
  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

在执行yum命令时忽然发现出现以下报错：

yum list

File "/usr/bin/yum", line 30

except KeyboardInterrupt, e:

                       ^

SyntaxError: invalid syntax

原因：

这是因为yum采用Python作为命令解释器，这可以从/usr/bin/yum文件中第一行#!/usr/bin/python发现。而python版本之间兼容性不太好，使得2.X版本与3.0版本之间存在语法不一致问题。而CentOS 7自带的yum采用的是python2.7，当系统将python升级到3.4后，出现语法解释错误。

解决办法：

一是升级yum。

二是修改yum的解释器为旧版本python2.7，即将连接文件/usr/bin/python连接回/usr/bin/python2.7。治标不治本，不推荐。

三是在设置里更改解释器设置，即修改/usr/bin/yum文件，指定使用python2.7作为yum的解释器：

将第一行”#!/usr/bin/python” 改为 “#!/usr/bin/python2″即可。

安装软件时又会出现另一种报错

Downloading packages:

  File "/usr/libexec/urlgrabber-ext-down", line 28

    except OSError, e:

                  ^

SyntaxError: invalid syntax

问题与前面一个一样，因此解决办法也是一样的：

vi /usr/libexec/urlgrabber-ext-down

将第一行”#!/usr/bin/python” 改为 “#!/usr/bin/python2″即可。