我在使用ubuntu11.04的时候，为了配置hadoop，使用root用户修改主机名:
gedit /etc/hostname;
gedit /etc/hosts;
修改的时候出现以下错误
我在使用gedit打开文件的时候，会提示一堆的警告：
(gedit:9778): Gtk-WARNING **: Attempting to store changes into `/root/.local/share/recently-used.xbel', but failed: Failed to create file '/root/.local/share/recently-used.xbel.LTBP3V': No such file or directory
(gedit:9778): Gtk-WARNING **: Attempting to set the permissions of `/root/.local/share/recently-used.xbel', but failed: No such file or directory
(gedit:9778): Gtk-WARNING **: Attempting to store changes into `/root/.local/share/recently-used.xbel', but failed: Failed to create file '/root/.local/share/recently-used.xbel.47P63V': No such file or directory
(gedit:9778): Gtk-WARNING **: Attempting to set the permissions of `/root/.local/share/recently-used.xbel', but failed: No such file or directory
(gedit:9778): Gtk-WARNING **: Attempting to store changes into `/root/.local/share/recently-used.xbel', but failed: Failed to create file '/root/.local/share/recently-used.xbel.MN6R3V': No such file or directory
(gedit:9778): Gtk-WARNING **: Attempting to set the permissions of `/root/.local/share/recently-used.xbel', but failed: No such file or directory
根据上面的提示，以及网上查的资料，知道的怎么解决：
直接在terminal中输入 sudo mkdir -p /root/.local/share/
也就是表示以超级用户（sudo命令）身份创建目录