关于EDM邮件涉及的MX记录、A记录和反向解析

本文主要描述：关于EDM邮件涉及的MX记录、A记录和反向解析 涉及到mx记录,mx记录查询,mx记录设置,查看mx记录,mx记录指向,怎么设置mx记录, 背景知识： 什么是MX记录？ 用于电子邮件系统发邮件时根据收信人的地址后缀来定位邮件服务器。例如，当收件人为“user@mydomain.com”时， 系统将对“mydomain.com”进行DNS中的MX记录解析。如果MX记录存在，系统就根据MX记录的优先级， 将邮件转发到与该MX相应的邮件服务器上。 什么是正向解析？ 比如你在万网注册的域名， www.55tuan.com ，在万网登录后域名管理界面上增加了一个MX记录，指向邮件服务器121.11.24.146。这就叫正向解析。 什么是A记录？ A (Address) 记录是用来指定主机名（或域名）对应的IP地址记录。用户可以将该域名下的网站服务器指向到自己的web server上。同时也可以设置域名的子域名。 什么是反向解析？ DNS服务器里有两个区域，“正向查找区域”和“反向查找区域”，反向查找区域即IP反向解析，它的作用就是通过查询IP地址的PTR记录来得到该IP地址指向的域名。 举例，用 info@news.gaopeng.com 作为发件人给用户邮箱 a@163.com 发邮件。网易的邮件服务器接到这封邮件，就会查看邮件头。邮件头里会显示这封邮件是由哪个IP地址发出来的，如： Received: from mta406.us.news.gaopeng.com(mta406.us.news.gaopeng.com [208.50.56.68]) 那么208.50.56.68就是发送邮件的SMTP服务器IP地址。然后根据这个IP地址进行反向解析，如果反向解析到这个IP所对应的域名确实是 mta406.us.news.gaopeng.com，那么就接受这封邮件。如果反向解析发现这个IP没有对应到 news.gaopeng.com ，那么就拒绝这封邮件。 注1：反向解析的域名的A记录一定要指向该IP。 注2：反向解析跟域名注册商无关，是给你分配IP地址的IDC机房做的。所以有时候会存在费用问题。 反向解析的过程在Windows下可以模拟为： 命令行：nslookup -qt=ptr 输入你要查的IP地址，如下所示： > 208.50.56.68 非权威应答: 68.56.50.208.in-addr.arpa name = mta406.us.news.gaopeng.com 什么是SPF记录： 全称是Sender Policy Framework，即发信者策略架构，通常直接称为SPF。　 SPF是为了防范垃圾邮件而提出来的一种DNS记录类型，它是一种TXT类型的记录，它用于登记某个域名拥有的用来外发邮件的所有IP地址。 举例，还是用nslookup查看美团的SPF记录： C:\>nslookup > set type=txt > meituan.com 非权威应答: meituan.com text = "v=spf1 ip4:58.83.134.224/27 ip4:59.151.43.32/27 ip4:211.151.229.32/27 i p4:211.151.229.64/26ip4:211.151.229.128/28 ip4:173.45.234.162 ip4:173.45.238.15 5 ip4:72.14.188.19include:aspmx.googlemail.com -all" 检查您的域名的MX解析记录设置是否正确的步骤如下 可以：在运行中输入cmd回车，打开命令提示符，输入nslookup -q=mx mydomain.com便可检查MX记录是否生效。 也可： 1) 在Windows系统中点击"开始"菜单→"运行"→"输入cmd"（Windows98系统为command），打开windows系统的MS-DOS界面。输入"nslookup"命令，进入域名解析界面。 2) 输入" set q=mx "回车，进入MX记录查询状态 输入您公司邮件服务器的主域名，即为用户邮件地址的"@"之后的部分 如：hichina.com等 本文以hiChina.com为例返回如下大致信息(蓝色部分为注释)： > hichina.com Server: 218.106.248.21 －－这是当前所使用的DNS主机名 Address: 218.106.248.21#53 －－这是当前所使用DNS主机地址 Non-authoritative answer: hichina.com mail exchanger = 10 mx.hichina.com. －－这是china.com的MX记录指向的主机名 3) 规范的MX记录应当由主域解析出一个主机名（本例中是mx.hichina.com），再由此主机名解析出一个或多个IP地址（本例中是221.122.57.45）。 4) 注意:域名解析修改和添加只是在域名提供商的个别DNS上修改，其他人所使用的DNS服务器未必和您申请域名解析的DNS服务器相同，因此当您的域名添加或者修改后，只有等DNS服务器之间资料同步后才能看到正确的解析结果。万网的解析记录设置完毕后的生效时间为60分钟。其它服务器一般解析生效时间在同一个地区的同步可能需要几小时，全国DNS同步可能需要1-2天，全球DNS同步可能需要更长时间，因此域名解析更改后无法立刻生效。

•   随手笔记
•   2017-05-21
•   评论
•   2087 次浏览

apache的ab命令压测

apache的ab命令压测： 2.在学习使用ab命令之前，首先要了解压力测试的几个概念：（自己可以上网查下具体的概念） 吞吐率（Requests per second） 概念：服务器并发处理能力的量化描述，单位是reqs/s，指的是某个并发用户数下单位时间内处理的请求数。某个并发用户数下单位时间内能处理的最大请求数，称之为最大吞吐率。 计算公式：总请求数 / 处理完成这些请求数所花费的时间，即 Request per second = Complete requests / Time taken for tests 并发连接数（The number of concurrent connections） 概念：某个时刻服务器所接受的请求数目，简单的讲，就是一个会话。 并发用户数（The number of concurrent users，Concurrency Level） 概念：要注意区分这个概念和并发连接数之间的区别，一个用户可能同时会产生多个会话，也即连接数。 用户平均请求等待时间（Time per request） 计算公式：处理完成所有请求数所花费的时间/ （总请求数 / 并发用户数），即 Time per request = Time taken for tests /（ Complete requests / Concurrency Level） 服务器平均请求等待时间（Time per request: across all concurrent requests） 计算公式：处理完成所有请求数所花费的时间 / 总请求数，即 Time taken for / testsComplete requests 可以看到，它是吞吐率的倒数。 同时，它也=用户平均请求等待时间/并发用户数，即 Time per request / Concurrency Level 3.ab工具的介绍 ab是apache自带的压力测试工具。ab非常实用，它不仅可以对apache服务器进行网站访问压力测试，也可以对或其它类型的服务器进行压力测试。比如nginx、tomcat、IIS等。 安装： 1.公司应该有程序员吧，可以安装一个wamp或者phpstudy，这样apache服务器和mysql数据库都有了，一举多得 文件位置：打开你安装的apache的位置：找到 bin文件夹下面的ab.exe 在该文件夹下打开命令行，输入 ab.exe -help 对上面的Options做下解释吧： -n即requests，用于指定压力测试总共的执行次数。 -c即concurrency，用于指定压力测试的并发数。 -t即timelimit，等待响应的最大时间(单位：秒)。 -b即windowsize，TCP发送/接收的缓冲大小(单位：字节)。 -p即postfile，发送POST请求时需要上传的文件，此外还必须设置-T参数。 -u即putfile，发送PUT请求时需要上传的文件，此外还必须设置-T参数。 -T即content-type，用于设置Content-Type请求头信息，例如：application/x-www-form-urlencoded，默认值为text/plain。 -v即verbosity，指定打印帮助信息的冗余级别。 -w以HTML表格形式打印结果。 -i使用HEAD请求代替GET请求。 -x插入字符串作为table标签的属性。 -y插入字符串作为tr标签的属性。 -z插入字符串作为td标签的属性。 -C添加cookie信息，例如："Apache=1234"(可以重复该参数选项以添加多个)。 -H添加任意的请求头，例如："Accept-Encoding: gzip"，请求头将会添加在现有的多个请求头之后(可以重复该参数选项以添加多个)。 -A添加一个基本的网络认证信息，用户名和密码之间用英文冒号隔开。 -P添加一个基本的代理认证信息，用户名和密码之间用英文冒号隔开。 -X指定使用的代理服务器和端口号，例如:"126.10.10.3:88"。 -V打印版本号并退出。 -k使用HTTP的KeepAlive特性。 -d不显示百分比。 -S不显示预估和警告信息。 -g输出结果信息到gnuplot格式的文件中。 -e输出结果信息到CSV格式的文件中。 -r指定接收到错误信息时不退出程序。 -h显示用法信息，其实就是ab -help。 4.实际测试： 5.分析上面的压测结果： Server Software: Apache/2.2.25 (服务器软件名称及版本信息) Server Hostname: www.xxx.com(服务器主机名) Server Port: 80 (服务器端口) Document Path: /lol (供测试的URL路径) Document Length: 0 bytes (供测试的URL返回的文档大小) Concurrency Level: 100 (并发数) Time taken for tests: 0.800 seconds (压力测试消耗的总时间) Complete requests: 100 (压力测试的的总次数) Failed requests: 0 (失败的请求数) Total transferred: 16342 bytes (传输的总数据量) HTML transferred: 0 bytes (HTML文档的总数据量) Requests per second: 125.03 [#/sec] (mean) (平均每秒的请求数) Time per request: 799.805 [ms] (mean) (所有并发用户(这里是100)都请求一次的平均时间) Time per request: 7.998 [ms] (mean, across all concurrent requests) (单个用户请求一次的平均时间) Transfer rate: 19.95 [Kbytes/sec] received (传输速率，单位：KB/s) 在上面的测试中，我们设置的压力测试总次数以及并发数并没有让服务器感觉到什么「压力」，现在我们再来看一个「压力山大」的执行命令：ab -n 1000 -c 100 localhost/index.php,这个时候apache就直接罢工——拒绝访问了： D:\study\Apache\bin>ab -n 100 -c100 http://www.xxx.com/lol; This is ApacheBench, Version 2.3 <$Revision: 1748469 $> Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/ Licensed to The Apache Software Foundation, http://www.apache.org/ 在上面的压力测试中，Apache使用的是默认配置，并没有经过任何优化措施处理。实际上，Apache在经过配置优化 后，只要服务器硬件够用，Apache服务器是能够撑起1000的并发量的。

•   随手笔记
•   2017-04-25
•   评论
•   2147 次浏览

我们，走散了

<span style="font-family:punctuation, 微软雅黑, tohoma;font-size:14px;">　　这似乎是今年头一次在这里写些东西。</span><br style="font-family:punctuation, 微软雅黑, tohoma;font-size:14px;" /> <span style="margin:0px;padding:0px;font-family:punctuation, 微软雅黑, tohoma;font-size:14px;">       我大概的翻看了一下，除了中间两年的空白，前几年还是留下了些东西，且不管是好是坏。<br /> <span style="margin:0px;padding:0px;">       那时候刻意的追逐华丽的辞藻，却反而显得有些字面意义上的知识匮乏，在整理之前的日记的时候我也发现了，似乎这样做会让我觉得很有成就感吧？那种刻意的、生硬的遣词造句，但是流露出来的是真感情。<br /> <span style="margin:0px;padding:0px;">       我极为讨厌按照别人给定的框架写东西，首先，我是个知识不多的小伙儿，懂得不多，非要让我弄个什么发言稿什么的那就是太高看我了，我只是想按自己的方式来记录一些东西，也许我可以说是写给未来的自己。这一点在以往的日记里就体现出来了，我偶尔写些日记，在一个算不上漂亮的大笔记本上，胡乱的瞎写，想到什么就是什么，不限于今天吃了什么饭，碰见了什么人，和姑娘讲了什么话。<br />        很庆幸我有一直坚持一些东西，让得现在的我有机会去完成给自己许下的承诺，承诺就像是给自己设定的坎儿，不迈过去内心是十分看不起自己的，曾答应自己写完回忆，却马马虎虎的凑了字数，二十来万字的内容及其的空荡荡，我不得不以现在的眼光去审视以往的自己，就像自我反省一样。<br />        我们随着时光的变迁，渐行渐远，时光模糊了你我的背影，生活又给背影罩上了浓雾，从此便真的陌路了。<br />        决定重写《歧望》是在前一段时间，那时候正处于整理笔记的尾声，笔记里有太多太多的东西想让我用文字表述出来，而写东西这件事儿我是不擅长的，但是我答应了自己，那就得给自己一个说法，如果连自己都能糊弄了事，那我真的就要质疑我存活的意义了。我不想去欺骗任何人，特别是姑娘，虽然我曾尝试摆脱单身，但是我不想欺瞒哄骗，我想建立自己的底线，姑娘欣赏这一品格尚可，不喜欢也罢，我只是想在活着的时候完成想要完成的梦想。<br /> <span style="margin:0px;padding:0px;">       重写《歧望》 ，更名为《我们，走散了》，依旧在起点首发。<br /> <span style="margin:0px;padding:0px;">       我想为将来的自己留下点什么可以回忆的东西，而这也仅仅是耗费了我日常休息的时间，写东西本身就是一个学习的过程，所以我愿意把这个活动进行下去，可能会有些缓慢，如果有不当之处还请多多指教。</span></span></span></span></span>

•   妄尘集
•   2017-04-05
•   评论
•   1834 次浏览

关于find命令的小折腾

<p class="MsoNormal"><span style="font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">昨天晚上写的脚本，今天搞了一天没有弄清楚执行的目录为什么不对，在群里和一些朋友讨论了半天，对我的语法严谨性做了批判，同时对我的变量调用不清晰做了一些指导，名称要简单直接，但是我在脚本里的目的是为了让备份后的东西看起来简单直接，如果代码里的东西简单直接了，后期的维护就比较难做，不过有一些建议我还是要</span><span style="font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">听取的，代码的整洁性必须要有，不仅仅是让自己看懂，对于操作的目的也应该简单的标识，对于复合的脚本采用函数包装，模块化操作，方便维护的同时保持代码的可读性。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal"><span lang="EN-US"> </span></p> <p class="MsoNormal"><span lang="EN-US">     </span><span style="font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">总之就是受教了，</span><span lang="EN-US">find</span><span style="font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">命令在操作对象前应加目录，如果是已经</span><span lang="EN-US">cd</span><span style="font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">到该目录则</span><span lang="EN-US">find ./</span><span style="font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">目标地址</span><span lang="EN-US">/</span><span style="font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">文件</span><span lang="EN-US"> -type</span><span style="font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">……如果没有</span><span lang="EN-US">cd</span><span style="font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">到该目录则写入完整目录。</span><span lang="EN-US"><o:p></o:p></span></p>

•   随手笔记
•   2017-03-25
•   评论
•   2164 次浏览

第八节——逻辑运算和正则表达式

<p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">逻辑运算：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span lang="EN-US">    0(true)    1(false)<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">&&  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">与运算</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">||   </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">或运算</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">!    </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">非运算</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">短路运算：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">A&&B  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">当</span><span lang="EN-US">A</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">为</span><span lang="EN-US">1</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">（假），结果必定为假</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">        </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">当</span><span lang="EN-US">A</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">为</span><span lang="EN-US">0</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">（真），</span><span lang="EN-US">B</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">必须要参与运算</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">A||B   </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">当</span><span lang="EN-US">A</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">为</span><span lang="EN-US">0</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">（真），结果必定为真</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">        </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">当</span><span lang="EN-US">A</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">为</span><span lang="EN-US">1</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">（假），</span><span lang="EN-US">B</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">必须要参与运算</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span lang="EN-US">linux</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">上文本处理三剑客：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#grep  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">文本过滤工具，基于模式（</span><span lang="EN-US">pattern</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">），显示匹配的行</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#sed   </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">流编辑器，是一个文本编辑工具，行编辑器</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#awk   linux</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">上实现的是</span><span lang="EN-US">gawk</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">，</span><span lang="EN-US">awk</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">也是一门单独的编程语言，也就是说，</span><span lang="EN-US">awk</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">可以作为一个解释器，</span><span lang="EN-US">awk</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">既不是用来编辑文本，也不是用来过滤文本，二是将文本进行美观输出，所以</span><span lang="EN-US">awk</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">是一个文本报告生成器。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">基本的正则表达式元字符：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">字符匹配元字符：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“.”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">匹配任意单个字符</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“[]” </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">匹配指定范围内的任意单个字符</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“[^]”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">匹配指定范围外的任意单个字符</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">[:lower:]  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">所有的小写字母</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">[:upper:]  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">所有的大写字母</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">[:alpha:]  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">所有的大小写字母</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">[:alnum:]  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">所有的字母和数字</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">[:punct:]  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">所有的特殊字符</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">[:space:]   </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">空格字符</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">文本处理工具使用的模式应当使用引号包含起来：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">双引号：弱引用，其中的变量会被替换</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">单引号：强引用，除了元字符，其他都当做字符处理。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">次数匹配元字符：用在要指定次数的字符后面，用于指定前面字符出现的次数。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“*”    </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">匹配前面的字符任意次，</span><span lang="EN-US">“*”</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">本身仅表示次数</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">例：</span><span lang="EN-US">grep   “a*b” filename  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">能匹配到的如下</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">   /etc/fstab  a</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">出现一次</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">   /boot     a</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">出现</span><span lang="EN-US">0</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">次</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">即</span><span lang="EN-US">a*b</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">表示的意义为，</span><span lang="EN-US">a</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">出现</span><span lang="EN-US">0</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">次、</span><span lang="EN-US">1</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">次或多次</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">正则匹配默认工作在贪婪模式下，最大匹配原则。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“.*”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">任意长度的任意字符。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“\?”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">匹配其前面的字符</span><span lang="EN-US">0</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">次或者</span><span lang="EN-US">1</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">次，即前面的字符可有可无。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“\+”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">匹配其前面的字符至少一次。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“\{m,n\}”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">匹配其前面字符，至少</span><span lang="EN-US">m</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">次，至多</span><span lang="EN-US">n</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">次。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“\{m\}”   </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">匹配前面的字符</span><span lang="EN-US">m</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">次。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“\{0,n}\”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">匹配前面的字符至多</span><span lang="EN-US">n</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">次。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“\{m,}\”   </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">匹配前面的字符至少</span><span lang="EN-US">m</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">次。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">位置锚定：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">^:</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">行首锚定，使用在最左侧。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">$:</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">行尾锚定，使用在最右侧。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">^PATTERN$:</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">用模式匹配整行，匹配到为真，匹配不到为假。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“^$”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">空行，</span><span lang="EN-US">none</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“^[[:space:]]*$”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">空白行（没有可见字符）。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“\<”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">词首锚定，用于单词的左侧。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“\b”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">词首锚定</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“\>”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">词尾锚定，用于单词的右侧。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“\b”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">词尾锚定</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“\<PATTERN\>”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">单词锚定，匹配整个单词</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“\bPATTERN\b”<o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">分组：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">“\(\)”  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">小括号在</span><span lang="EN-US">shell</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">中有特殊意义，所以转义，将一段字符当作一个整体处理。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">字符一旦分组以后，在所有的正则表达式当中还有第二个作用。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">后项引用：引用前面分组括号中模式所匹配的字符，一旦一个模式匹配到衣蛾字符串了，在后面的任何位置我们都可以再次引用这个模式所匹配到的字符。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">Tip</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">：分组括号中的模式匹配到的内容会被正则表达式引擎记录于内部的变量中，这些变量的命名的方式为</span><span lang="EN-US">\1,\2,\3</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">等等。</span><span lang="EN-US">\1</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">表示从左侧起第一个左括号到与之匹配的右括号之间模式所匹配到的字符，此处允许嵌套，最里面的一对括号算最后一个。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">egg</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">：</span><span lang="EN-US">\(ab\+\(xy\)*\)<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">\1 </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">匹配</span> <span lang="EN-US">ab\+\(xy\)*<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">\2 </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">匹配</span> <span lang="EN-US">xy<o:p></o:p></span></p> <span style="font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times Newroman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:en-us;mso-fareast-language:zh-cn;mso-bidi-language:ar-sa;">我们在这里再次提示，后向引用的引用方式：引用的是前面分组括号中的模式所匹配到的字符，而非模式本身。</span>

•   基础笔记二
•   2017-03-24
•   评论
•   2698 次浏览

第七节——权限管理

<p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">权限主要针对三类用户定义：属主</span><span lang="EN-US">u</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">（前三位）、属组</span><span lang="EN-US">g</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">（中间三位）、其他人</span><span lang="EN-US">o</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">（后三位）</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">每个文件针对每类访问者都定义了三种权限。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">对文件来说：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">r readable  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">拥有读权限的文件，可以使用文件查看工具获取其内容</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">w writable  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">拥有写权限的文件，可以修改其中的内容</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">x excuable  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">拥有执行权限的文件，可以将此文件提请内核启动为一个进程</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">对目录来说：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">r </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">拥有读权限，可以使用</span><span lang="EN-US">ls</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">查看目录中的文件列表</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">w </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">拥有写权限，可以在此目录下创建、删除文件</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">x </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">拥有执行权限，可以</span><span lang="EN-US">cd</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">到此目录，也可以使用</span><span lang="EN-US">ls –l</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">查看此目录中的文件列表。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">权限位与八进制的对应：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">---  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">无权限</span><span lang="EN-US">       000 0<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">--x  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">执行权限</span><span lang="EN-US">     001  1<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">-w- </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">写权限</span><span lang="EN-US">       010 2<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">-wx </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">写、执行</span> <span lang="EN-US">    011  3<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">r--  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">读权限</span><span lang="EN-US">       100 4<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">r-x  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">读、执行</span><span lang="EN-US">    101  5<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">rw-  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">读写</span><span lang="EN-US">        110  6<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">rwx  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">读写执行</span><span lang="EN-US">    111  7<o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">文件权限的修改：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#chmod  [option]... MODE  file </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">修改文件的权限</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">使用八进制数字形式：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">更改目录权限时默认不会更改目录下文件的权限，递归修改需要使用</span><span lang="EN-US">-R</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">选项，递归修改目录下的权限。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#chmod 750  /tmp/test1<o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">直接指定</span><span lang="EN-US">mode</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">进行定义：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#chmod  u=rw,g=r,o= filename or dir  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">使用逗号隔开</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#chmod  ug=rw,o=r filename or dir   </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">当权限位一样时可以合并</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#chmod  all=rw</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">（</span><span lang="EN-US">a=rw</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">）</span><span lang="EN-US">  filename  or  dir</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">可以使用</span><span lang="EN-US">all</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">同时定义相同的三类权限。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">修改某类用户或者某些位的权限：</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#chmod  u+x filename or dir  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">给属主增加执行权限</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#chmod  g-w filename or dir  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">给属组减去写权限</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#chmod  ug-w filename or dir </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">给属主属组减去写权限</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#chmod  a+r  filename  or  dir </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">给所有人加上读取权限</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">参考其他文件的权限，将其他文件的权限赋予当前文件</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#chmod  --reference=/etc/fstab  /tmp/test1<o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">修改用户的属主属组，仅管理员</span><span lang="EN-US">root</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">可以使用</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#chown  hadoop:hadoop /tmp/test2  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">将</span><span lang="EN-US">/tmp/test2</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">文件的属主属组修改为</span><span lang="EN-US">hadoop<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#chown  :hadoop /tmp/test3  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">将</span><span lang="EN-US">/tmp/test3</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">文件的属组修改为</span><span lang="EN-US">hadoop<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US"> -R  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">递归修改目录下的所有文件</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US"> --refence=filename  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">参照文件修改权限</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#chgrp  group filename  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">修改文件的属组</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US"> -R  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">递归修改文件的属组</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">为什么我们创建文件和目录的时候都有一个默认的权限？这个权限可不可以被修改？</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">实现默认权限的指派是因为遮罩码（</span><span lang="EN-US">umask</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">）</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">遮罩码是反向运用的</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">创建文件的时候，默认权限的指派方式为：</span><span lang="EN-US"><br />       666-umask<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">如果文件存在执行权限，则其对应八进制权限</span><span lang="EN-US">+1</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">后赋予新权限，也就是说，新创建的文件不允许拥有执行权限。</span><span lang="EN-US"><o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">创建目录时，默认权限的指派方式为：</span><span lang="EN-US"><br />        777-umask<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">root</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">用户的</span><span lang="EN-US">umask</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">遮罩码为</span><span lang="EN-US">022<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">普通用户的</span><span lang="EN-US">umask</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">遮罩码为</span><span lang="EN-US">002<o:p></o:p></span></p> <p class="MsoNormal" align="left" style="text-indent:21pt;"><span lang="EN-US">#umask  ###  </span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">指定遮罩码，</span><span lang="EN-US">umask</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">的设定仅对当前用户的当前</span><span lang="EN-US">shell</span><span style="mso-bidi-font-size:10.5pt;font-family:宋体;mso-ascii-font-family:calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:宋体;mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:calibri;mso-hansi-theme-font:minor-latin;">有效</span><span lang="EN-US"><o:p></o:p></span></p>

•   基础笔记二
•   2017-03-23
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•   2576 次浏览

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