请问为何提示没有发现软件包呢

[mrfox]

按http://how-to.cc/get-a-displaylink-video-adapter-working-with-ubuntu-12-04这里的教程运行apt-get install xserver-xorg-video-displaylink提示找不到软件包

于是搜索，找到http://packages.ubuntu.com/zh-cn/precise/amd64/xserver-xorg-video-displaylink/download
参照它添加了一句deb https://launchpad.net/ubuntu/+mirror/ft ... cn-archive precise main universe
后update了下

但是运行deb https://launchpad.net/ubuntu/+mirror/ft ... cn-archive precise main universe
仍然提示E: 未发现软件包 xserver-xorg-video-displaylink

我的ubuntu版本是15.04

[qy117121]

precise 这个是12.04啊，
你是15.04的话要换成15.04的代号啊
vivid 这个是15.04 的

[mrfox]

precise 这个是12.04啊，
你是15.04的话要换成15.04的代号啊
vivid 这个是15.04 的

原来是这个意思，感谢！不过

代码： 全选

sudo apt-get update
命中 http://cn.archive.ubuntu.com vivid InRelease
命中 http://cn.archive.ubuntu.com vivid-updates InRelease                      
命中 http://cn.archive.ubuntu.com vivid-backports InRelease                    
忽略 http://ppa.launchpad.net vivid InRelease                                  
命中 http://ppa.launchpad.net vivid InRelease
获取：1 http://security.ubuntu.com vivid-security InRelease [65.9 kB]          
忽略 http://ppa.launchpad.net vivid Release.gpg                              
获取：2 http://cn.archive.ubuntu.com vivid-updates/main Sources [112 kB]
获取：3 http://cn.archive.ubuntu.com vivid-updates/restricted Sources [4,351 B]
获取：4 http://cn.archive.ubuntu.com vivid-updates/universe Sources [51.7 kB]  
获取：5 http://cn.archive.ubuntu.com vivid-updates/multiverse Sources [2,406 B]
获取：6 http://cn.archive.ubuntu.com vivid-updates/main amd64 Packages [289 kB]
获取：7 http://cn.archive.ubuntu.com vivid-updates/restricted amd64 Packages [13.6 kB]
获取：8 http://cn.archive.ubuntu.com vivid-updates/universe amd64 Packages [138 kB]
获取：9 http://cn.archive.ubuntu.com vivid-updates/multiverse amd64 Packages [6,028 B]
获取：10 http://cn.archive.ubuntu.com vivid-updates/main i386 Packages [285 kB]
获取：11 http://cn.archive.ubuntu.com vivid-updates/restricted i386 Packages [13.3 kB]
获取：12 http://cn.archive.ubuntu.com vivid-updates/universe i386 Packages [138 kB]
获取：13 http://cn.archive.ubuntu.com vivid-updates/multiverse i386 Packages [6,502 B]
获取：14 http://cn.archive.ubuntu.com vivid-updates/main Translation-en [137 kB]
获取：15 http://cn.archive.ubuntu.com vivid-updates/multiverse Translation-en [3,120 B]
忽略 http://ppa.launchpad.net vivid Release                                    
获取：16 http://cn.archive.ubuntu.com vivid-updates/restricted Translation-en [3,112 B]
获取：17 http://cn.archive.ubuntu.com vivid-updates/universe Translation-en [81.6 kB]
获取：18 http://security.ubuntu.com vivid-security/main Sources [59.7 kB]      
命中 http://ppa.launchpad.net vivid/main amd64 Packages                        
命中 http://cn.archive.ubuntu.com vivid-backports/restricted Sources           
命中 http://cn.archive.ubuntu.com vivid-backports/multiverse Sources           
命中 http://cn.archive.ubuntu.com vivid-backports/restricted amd64 Packages   
命中 http://ppa.launchpad.net vivid/main i386 Packages                  
命中 http://cn.archive.ubuntu.com vivid-backports/multiverse amd64 Packages   
命中 http://cn.archive.ubuntu.com vivid-backports/restricted i386 Packages
命中 http://ppa.launchpad.net vivid/main Translation-en                 
命中 http://cn.archive.ubuntu.com vivid-backports/multiverse i386 Packages     
命中 http://cn.archive.ubuntu.com vivid-backports/multiverse Translation-en   
命中 http://cn.archive.ubuntu.com vivid-backports/restricted Translation-en   
命中 http://cn.archive.ubuntu.com vivid/main Sources                           
命中 http://cn.archive.ubuntu.com vivid/restricted Sources                     
命中 http://cn.archive.ubuntu.com vivid/universe Sources                       
命中 http://cn.archive.ubuntu.com vivid/multiverse Sources                     
命中 http://cn.archive.ubuntu.com vivid/main amd64 Packages                    
命中 http://cn.archive.ubuntu.com vivid/restricted amd64 Packages              
命中 http://cn.archive.ubuntu.com vivid/universe amd64 Packages                
命中 http://cn.archive.ubuntu.com vivid/multiverse amd64 Packages              
命中 http://cn.archive.ubuntu.com vivid/main i386 Packages                     
命中 http://cn.archive.ubuntu.com vivid/restricted i386 Packages               
命中 http://cn.archive.ubuntu.com vivid/universe i386 Packages                 
命中 http://cn.archive.ubuntu.com vivid/multiverse i386 Packages               
命中 http://cn.archive.ubuntu.com vivid/main Translation-zh_CN                 
获取：19 https://launchpad.net vivid InRelease [9,984 B]                       
命中 http://cn.archive.ubuntu.com vivid/main Translation-en                    
忽略 https://launchpad.net vivid InRelease                                     
命中 http://cn.archive.ubuntu.com vivid/multiverse Translation-zh_CN           
命中 http://cn.archive.ubuntu.com vivid/multiverse Translation-en              
命中 http://cn.archive.ubuntu.com vivid/restricted Translation-zh_CN           
命中 http://cn.archive.ubuntu.com vivid/restricted Translation-en              
命中 http://cn.archive.ubuntu.com vivid/universe Translation-zh_CN             
命中 http://cn.archive.ubuntu.com vivid/universe Translation-en                
命中 http://cn.archive.ubuntu.com vivid-backports/main Sources                 
命中 http://cn.archive.ubuntu.com vivid-backports/universe Sources
命中 http://cn.archive.ubuntu.com vivid-backports/main amd64 Packages
命中 http://cn.archive.ubuntu.com vivid-backports/universe amd64 Packages
获取：20 https://launchpad.net vivid Release.gpg [9,984 B]                     
命中 http://cn.archive.ubuntu.com vivid-backports/main i386 Packages           
命中 http://cn.archive.ubuntu.com vivid-backports/universe i386 Packages       
命中 http://cn.archive.ubuntu.com vivid-backports/main Translation-en          
命中 http://cn.archive.ubuntu.com vivid-backports/universe Translation-en      
获取：21 http://security.ubuntu.com vivid-security/restricted Sources [3,418 B]
忽略 https://launchpad.net vivid Release.gpg                                   
获取：22 http://security.ubuntu.com vivid-security/universe Sources [24.3 kB]  
获取：23 http://security.ubuntu.com vivid-security/multiverse Sources [1,942 B]
获取：24 https://launchpad.net vivid Release [9,984 B]                         
获取：25 http://security.ubuntu.com vivid-security/main amd64 Packages [198 kB]
忽略 https://launchpad.net vivid Release                                       
获取：26 https://launchpad.net vivid/main amd64 Packages [9,984 B]             
获取：27 https://launchpad.net vivid/universe amd64 Packages [9,984 B]         
获取：28 https://launchpad.net vivid/main i386 Packages [9,984 B]              
错误 http://ppa.launchpad.net vivid/main amd64 Packages                        
  404  Not Found
获取：29 http://security.ubuntu.com vivid-security/restricted amd64 Packages [11.2 kB]
错误 http://ppa.launchpad.net vivid/main i386 Packages                         
  404  Not Found
忽略 http://ppa.launchpad.net vivid/main Translation-zh_CN                     
获取：30 https://launchpad.net vivid/universe i386 Packages [9,984 B]          
忽略 http://ppa.launchpad.net vivid/main Translation-zh                        
忽略 http://ppa.launchpad.net vivid/main Translation-en                        
获取：31 https://launchpad.net vivid/main Translation-zh_CN [9,984 B]          
获取：32 http://security.ubuntu.com vivid-security/universe amd64 Packages [77.0 kB]
获取：33 https://launchpad.net vivid/main Translation-zh [9,984 B]             
获取：34 http://security.ubuntu.com vivid-security/multiverse amd64 Packages [6,028 B]
获取：35 https://launchpad.net vivid/main Translation-en [9,984 B]             
获取：36 http://security.ubuntu.com vivid-security/main i386 Packages [195 kB] 
获取：37 https://launchpad.net vivid/universe Translation-zh_CN [9,984 B]      
获取：38 https://launchpad.net vivid/universe Translation-zh [9,984 B]         
获取：39 https://launchpad.net vivid/universe Translation-en [9,984 B]         
获取：40 http://security.ubuntu.com vivid-security/restricted i386 Packages [10.9 kB]
获取：41 http://security.ubuntu.com vivid-security/universe i386 Packages [77.0 kB]
获取：42 https://launchpad.net vivid/main amd64 Packages [9,984 B]             
获取：43 https://launchpad.net vivid/universe amd64 Packages [9,984 B]         
获取：44 http://security.ubuntu.com vivid-security/multiverse i386 Packages [6,197 B]
获取：45 https://launchpad.net vivid/main i386 Packages [9,984 B]              
获取：46 https://launchpad.net vivid/universe i386 Packages [9,984 B]          
获取：47 https://launchpad.net vivid/main Translation-zh_CN [9,984 B]          
获取：48 https://launchpad.net vivid/main Translation-zh [9,984 B]             
获取：49 https://launchpad.net vivid/main Translation-en [9,984 B]             
获取：50 https://launchpad.net vivid/universe Translation-zh_CN [9,984 B]      
命中 http://security.ubuntu.com vivid-security/main Translation-en  
命中 http://security.ubuntu.com vivid-security/multiverse Translation-en       
命中 http://security.ubuntu.com vivid-security/restricted Translation-en       
获取：51 https://launchpad.net vivid/universe Translation-zh [9,984 B]         
命中 http://security.ubuntu.com vivid-security/universe Translation-en         
获取：52 https://launchpad.net vivid/universe Translation-en [9,984 B]         
获取：53 https://launchpad.net vivid/main amd64 Packages [9,984 B]             
获取：54 https://launchpad.net vivid/universe amd64 Packages [9,984 B]         
获取：55 https://launchpad.net vivid/main i386 Packages [9,984 B]              
获取：56 https://launchpad.net vivid/universe i386 Packages [9,984 B]          
获取：57 https://launchpad.net vivid/main Translation-zh_CN [9,984 B]          
获取：58 https://launchpad.net vivid/main Translation-zh [9,984 B]             
获取：59 https://launchpad.net vivid/main Translation-en [9,984 B]             
获取：60 https://launchpad.net vivid/universe Translation-zh_CN [9,984 B]      
获取：61 https://launchpad.net vivid/universe Translation-zh [9,984 B]         
获取：62 https://launchpad.net vivid/universe Translation-en [9,984 B]         
获取：63 https://launchpad.net vivid/main amd64 Packages [9,984 B]             
获取：64 https://launchpad.net vivid/universe amd64 Packages [9,984 B]         
获取：65 https://launchpad.net vivid/main i386 Packages [9,984 B]              
获取：66 https://launchpad.net vivid/universe i386 Packages [9,984 B]          
获取：67 https://launchpad.net vivid/main Translation-zh_CN [9,984 B]          
获取：68 https://launchpad.net vivid/main Translation-zh [9,984 B]             
获取：69 https://launchpad.net vivid/main Translation-en [9,984 B]             
获取：70 https://launchpad.net vivid/universe Translation-zh_CN [9,984 B]      
获取：71 https://launchpad.net vivid/universe Translation-zh [9,984 B]         
获取：72 https://launchpad.net vivid/universe Translation-en [9,984 B]         
获取：73 https://launchpad.net vivid/main amd64 Packages [9,984 B]             
错误 https://launchpad.net vivid/main amd64 Packages                           
  HttpError404
获取：74 https://launchpad.net vivid/universe amd64 Packages [9,984 B]         
错误 https://launchpad.net vivid/universe amd64 Packages                       
  HttpError404
获取：75 https://launchpad.net vivid/main i386 Packages [9,984 B]              
错误 https://launchpad.net vivid/main i386 Packages                            
  HttpError404
获取：76 https://launchpad.net vivid/universe i386 Packages [9,984 B]          
错误 https://launchpad.net vivid/universe i386 Packages                        
  HttpError404
获取：77 https://launchpad.net vivid/main Translation-zh_CN [9,984 B]          
忽略 https://launchpad.net vivid/main Translation-zh_CN                        
获取：78 https://launchpad.net vivid/main Translation-zh [9,984 B]             
忽略 https://launchpad.net vivid/main Translation-zh                           
获取：79 https://launchpad.net vivid/main Translation-en [9,984 B]             
忽略 https://launchpad.net vivid/main Translation-en                           
获取：80 https://launchpad.net vivid/universe Translation-zh_CN [9,984 B]      
忽略 https://launchpad.net vivid/universe Translation-zh_CN                    
获取：81 https://launchpad.net vivid/universe Translation-zh [9,984 B]         
忽略 https://launchpad.net vivid/universe Translation-zh                       
获取：82 https://launchpad.net vivid/universe Translation-en [9,984 B]         
忽略 https://launchpad.net vivid/universe Translation-en                       
下载 961 kB，耗时 45秒 (21.2 kB/s)                                             
W: 无法下载 http://ppa.launchpad.net/fcitx-team/nightly/ubuntu/dists/vivid/main/binary-amd64/Packages  404  Not Found

W: 无法下载 http://ppa.launchpad.net/fcitx-team/nightly/ubuntu/dists/vivid/main/binary-i386/Packages  404  Not Found

W: 无法下载 https://launchpad.net/ubuntu/+mirror/ftp.sjtu.edu.cn-archive/dists/vivid/main/binary-amd64/Packages  HttpError404

W: 无法下载 https://launchpad.net/ubuntu/+mirror/ftp.sjtu.edu.cn-archive/dists/vivid/universe/binary-amd64/Packages  HttpError404

W: 无法下载 https://launchpad.net/ubuntu/+mirror/ftp.sjtu.edu.cn-archive/dists/vivid/main/binary-i386/Packages  HttpError404

W: 无法下载 https://launchpad.net/ubuntu/+mirror/ftp.sjtu.edu.cn-archive/dists/vivid/universe/binary-i386/Packages  HttpError404

E: 部分索引文件下载失败。如果忽略它们，那将转而使用旧的索引文件。
h@g:~$ apt-get install xserver-xorg-video-displaylink
E: 无法打开锁文件 /var/lib/dpkg/lock - open (13: 权限不够)
E: 无法对状态列表目录加锁(/var/lib/dpkg/)，请查看您是否正以 root 用户运行？
h@g:~$ sudo apt-get install xserver-xorg-video-displaylink
正在读取软件包列表... 完成
正在分析软件包的依赖关系树       
正在读取状态信息... 完成       
E: 未发现软件包 xserver-xorg-video-displaylink

[vickycq]

W: 无法下载 https://launchpad.net/ubuntu/+mirror/ft ... 4/Packages HttpError404

这个地址确实不存在
尚未找到为 15.04 构建的 xserver-xorg-video-displaylink*.deb

看看这一篇 有没有帮助：https://www.mail-archive.com/kernel-pac ... 30685.html
从官网手动下载安装