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提高 WordPress 性能的9个技巧
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深入浅出讲述提升 WordPress 性能的九大秘笈
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================================================================================
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关于建站和 web 应用程序交付，WordPress 是全球最大的一个平台。全球大约 [四分之一][1] 的站点现在正在使用开源 WordPress 软件，包括 eBay, Mozilla, RackSpace, TechCrunch, CNN, MTV,纽约时报，华尔街日报。
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在建站和 web 应用程序交付方面，WordPress 是全球最大的一个平台。全球大约[四分之一][1] 的站点现在正在使用开源 WordPress 软件，包括 eBay、 Mozilla、 RackSpace、 TechCrunch、 CNN、 MTV、纽约时报、华尔街日报 等等。
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WordPress.com，对于用户创建博客平台是最流行的，其也运行在WordPress 开源软件上。[NGINX powers WordPress.com][2]。许多 WordPress 用户刚开始在 WordPress.com 上建站，然后移动到搭载着 WordPress 开源软件的托管主机上;其中大多数站点都使用 NGINX 软件。
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最流行的个人博客平台 WordPress.com，其也运行在 WordPress 开源软件上。[而 NGINX 则为 WordPress.com 提供了动力][2]。在 WordPress.com 的用户当中，许多站点起步于 WordPress.com，然后换成了自己运行 WordPress 开源软件；它们中越来越多的站点也使用了 NGINX 软件。
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WordPress 的吸引力是它的简单性，无论是安装启动或者对于终端用户的使用。然而，当使用量不断增长时，WordPress 站点的体系结构也存在一定的问题 - 这里几个方法，包括使用缓存以及组合 WordPress 和 NGINX，可以解决这些问题。
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WordPress 的吸引力源于其简单性，无论是对于最终用户还是安装架设。然而，当使用量不断增长时，WordPress 站点的体系结构也存在一定的问题 - 这里有几个方法，包括使用缓存，以及将 WordPress 和 NGINX 组合起来，可以解决这些问题。
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在这篇博客中，我们提供了9个技巧来进行优化，以帮助你解决 WordPress 中一些常见的性能问题：
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在这篇博客中，我们提供了九个提速技巧来帮助你解决 WordPress 中一些常见的性能问题：
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- [缓存静态资源][3]
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- [缓存动态文件][4]
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- [使用 NGINX][5]
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- [添加支持 NGINX 的链接][6]
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- [迁移到 NGINX][5]
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- [添加 NGINX 静态链接支持][6]
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- [为 NGINX 配置 FastCGI][7]
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- [为 NGINX 配置 W3_Total_Cache][8]
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- [为 NGINX 配置 WP-Super-Cache][9]
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@ -22,39 +21,39 @@ WordPress 的吸引力是它的简单性，无论是安装启动或者对于终
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### 在 LAMP 架构下 WordPress 的性能 ###
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大多数 WordPress 站点都运行在传统的 LAMP 架构下：Linux 操作系统，Apache Web 服务器软件，MySQL 数据库软件 - 通常是一个单独的数据库服务器 - 和 PHP 编程语言。这些都是非常著名的，广泛应用的开源工具。大多数人都将 WordPress “称为” LAMP，并且很容易寻求帮助和支持。
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大多数 WordPress 站点都运行在传统的 LAMP 架构下：Linux 操作系统，Apache Web 服务器软件，MySQL 数据库软件（通常是一个单独的数据库服务器）和 PHP 编程语言。这些都是非常著名的，广泛应用的开源工具。在 WordPress 世界里，很多人都用的是 LAMP，所以很容易寻求帮助和支持。
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当用户访问 WordPress 站点时，浏览器为每个用户创建六到八个连接来运行 Linux/Apache 的组合。当用户请求连接时，每个页面的 PHP 文件开始飞速的从 MySQL 数据库争夺资源来响应请求。
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当用户访问 WordPress 站点时，浏览器为每个用户创建六到八个连接来连接到 Linux/Apache 上。当用户请求连接时，PHP 即时生成每个页面，从 MySQL 数据库获取资源来响应请求。
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LAMP 对于数百个并发用户依然能照常工作。然而，流量突然增加是常见的并且 - 通常是 - 一件好事。
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LAMP 或许对于数百个并发用户依然能照常工作。然而，流量突然增加是常见的，并且通常这应该算是一件好事。
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但是，当 LAMP 站点变得繁忙时，当同时在线的用户达到数千个时，它的瓶颈就会被暴露出来。瓶颈存在主要是两个原因：
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1. Apache Web 服务器 - Apache 为每一个连接需要消耗大量资源。如果 Apache 接受了太多的并发连接，内存可能会耗尽，性能急剧降低，因为数据必须使用磁盘进行交换。如果以限制连接数来提高响应时间，新的连接必须等待，这也导致了用户体验变得很差。
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1. Apache Web 服务器 - Apache 的每个/每次连接需要消耗大量资源。如果 Apache 接受了太多的并发连接，内存可能会耗尽，从而导致性能急剧降低，因为数据必须交换到磁盘了。如果以限制连接数来提高响应时间，新的连接必须等待，这也导致了用户体验变得很差。
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1. PHP/MySQL 的交互 - 总之，一个运行 PHP 和 MySQL 数据库服务器的应用服务器上每秒的请求量不能超过最大限制。当请求的数量超过最大连接数时，用户必须等待。超过最大连接数时也会增加所有用户的响应时间。超过其两倍以上时会出现明显的性能问题。
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1. PHP/MySQL 的交互 - 一个运行 PHP 和 MySQL 数据库服务器的应用服务器上每秒的请求量有一个最大限制。当请求的数量超过这个最大限制时，用户必须等待。超过这个最大限制时也会增加所有用户的响应时间。超过其两倍以上时会出现明显的性能问题。
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LAMP 架构的网站一般都会出现性能瓶颈，这时就需要升级硬件了 - 加 CPU，扩大磁盘空间等等。当 Apache 和 PHP/MySQL 的架构负载运行后，在硬件上不断的提升无法保证对系统资源指数增长的需求。
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LAMP 架构的网站出现性能瓶颈是常见的情况，这时就需要升级硬件了 - 增加 CPU，扩大磁盘空间等等。当 Apache 和 PHP/MySQL 的架构超载后，在硬件上不断的提升却跟不上系统资源指数增长的需求。
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最先取代 LAMP 架构的是 LEMP 架构 – Linux, NGINX, MySQL, 和 PHP。 (这是 LEMP 的缩写，E 代表着 “engine-x.” 的发音。) 我们在 [技巧 3][12] 中会描述 LEMP 架构。
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首选替代 LAMP 架构的是 LEMP 架构 – Linux, NGINX, MySQL, 和 PHP。 (这是 LEMP 的缩写，E 代表着 “engine-x.” 的发音。) 我们在 [技巧 3][12] 中会描述 LEMP 架构。
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### 技巧 1. 缓存静态资源 ###
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静态资源是指不变的文件，像 CSS，JavaScript 和图片。这些文件往往在网页的数据中占半数以上。页面的其余部分是动态生成的，像在论坛中评论，仪表盘的性能，或个性化的内容（可以看看Amazon.com 产品）。
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静态资源是指不变的文件，像 CSS，JavaScript 和图片。这些文件往往在网页的数据中占半数以上。页面的其余部分是动态生成的，像在论坛中评论，性能仪表盘，或个性化的内容（可以看看 Amazon.com 产品）。
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缓存静态资源有两大好处：
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- 更快的交付给用户 - 用户从他们浏览器的缓存或者从互联网上离他们最近的缓存服务器获取静态文件。有时候文件较大，因此减少等待时间对他们来说帮助很大。
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- 更快的交付给用户 - 用户可以从它们浏览器的缓存或者从互联网上离它们最近的缓存服务器获取静态文件。有时候文件较大，因此减少等待时间对它们来说帮助很大。
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- 减少应用服务器的负载 - 从缓存中检索到的每个文件会让 web 服务器少处理一个请求。你的缓存越多，用户等待的时间越短。
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要让浏览器缓存文件，需要早在静态文件中设置正确的 HTTP 首部。当看到 HTTP Cache-Control 首部时，特别设置了 max-age，Expires 首部，以及 Entity 标记。[这里][13] 有详细的介绍。
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要让浏览器缓存文件，需要在静态文件中设置正确的 HTTP 首部。看看 HTTP Cache-Control 首部，特别是设置了 max-age 参数，Expires 首部，以及 Entity 标记。[这里][13] 有详细的介绍。
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当启用本地缓存然后用户请求以前访问过的文件时，浏览器首先检查该文件是否在缓存中。如果在，它会询问 Web 服务器该文件是否改变过。如果该文件没有改变，Web 服务器将立即响应一个304状态码（未改变），这意味着该文件没有改变，而不是返回状态码200 OK，然后继续检索并发送已改变的文件。
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当启用本地缓存，然后用户请求以前访问过的文件时，浏览器首先检查该文件是否在缓存中。如果在，它会询问 Web 服务器该文件是否改变过。如果该文件没有改变，Web 服务器将立即响应一个304状态码（未改变），这意味着该文件没有改变，而不是返回状态码200 OK 并检索和发送已改变的文件。
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为了支持浏览器以外的缓存，可以考虑下面的方法，内容分发网络（CDN）。CDN 是一种流行且强大的缓存工具，但我们在这里不详细描述它。可以想一下 CDN 背后的支撑技术的实现。此外，当你的站点从 HTTP/1.x 过渡到 HTTP/2 协议时，CDN 的用处可能不太大;根据需要调查和测试，找到你网站需要的正确方法。
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要在浏览器之外支持缓存，可以考虑下面讲到的技巧，以及考虑使用内容分发网络（CDN）。CDN 是一种流行且强大的缓存工具，但我们在这里不详细描述它。在你实现了这里讲到的其它技术之后可以考虑 CDN。此外，当你的站点从 HTTP/1.x 过渡到 HTTP/2 协议时，CDN 的用处可能不太大；根据需要调查和测试，找到你网站需要的正确方法。
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如果你转向 NGINX Plus 或开源的 NGINX 软件作为架构的一部分，建议你考虑 [技巧 3][14]，然后配置 NGINX 缓存静态资源。使用下面的配置，用你 Web 服务器的 URL 替换 www.example.com。
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如果你转向 NGINX Plus 或将开源的 NGINX 软件作为架构的一部分，建议你考虑 [技巧 3][14]，然后配置 NGINX 缓存静态资源。使用下面的配置，用你 Web 服务器的 URL 替换 www.example.com。
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server {
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# substitute your web server's URL for www.example.com
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@ -86,63 +85,63 @@ LAMP 对于数百个并发用户依然能照常工作。然而，流量突然增
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### 技巧 2. 缓存动态文件 ###
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WordPress 是动态生成的网页，这意味着每次请求时它都要生成一个给定的网页（即使和前一次的结果相同）。这意味着用户随时获得的是最新内容。
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WordPress 动态地生成网页，这意味着每次请求时它都要生成一个给定的网页（即使和前一次的结果相同）。这意味着用户随时获得的是最新内容。
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想一下，当用户访问一个帖子时，并在文章底部有用户的评论时。你希望用户能够看到所有的评论 - 即使评论刚刚发布。动态内容就是处理这种情况的。
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但现在，当帖子每秒出现十几二十几个请求时。应用服务器可能每秒需要频繁生成页面导致其压力过大，造成延误。为了给用户提供最新的内容，每个访问理论上都是新的请求，因此他们也不得不在首页等待。
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但现在，当帖子每秒出现十几二十几个请求时。应用服务器可能每秒需要频繁生成页面导致其压力过大，造成延误。为了给用户提供最新的内容，每个访问理论上都是新的请求，因此它们不得不在原始出处等待很长时间。
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为了防止页面由于负载过大变得缓慢，需要缓存动态文件。这需要减少文件的动态内容来提高整个系统的响应速度。
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为了防止页面由于不断提升的负载而变得缓慢，需要缓存动态文件。这需要减少文件的动态内容来提高整个系统的响应速度。
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要在 WordPress 中启用缓存中，需要使用一些流行的插件 - 如下所述。WordPress 的缓存插件需要刷新页面，然后将其缓存短暂时间 - 也许只有几秒钟。因此，如果该网站每秒中只有几个请求，那大多数用户获得的页面都是缓存的副本。这也有助于提高所有用户的检索时间：
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要在 WordPress 中启用缓存中，需要使用一些流行的插件 - 如下所述。WordPress 的缓存插件会请求最新的页面，然后将其缓存短暂时间 - 也许只有几秒钟。因此，如果该网站每秒中会有几个请求，那大多数用户获得的页面都是缓存的副本。这也有助于提高所有用户的检索时间：
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- 大多数用户获得页面的缓存副本。应用服务器没有做任何工作。
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- 用户很快会得到一个新的副本。应用服务器只需每隔一段时间刷新页面。当服务器产生一个新的页面（对于第一个用户访问后，缓存页过期），它这样做要快得多，因为它的请求不会超载。
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- 用户会得到一个之前的崭新副本。应用服务器只需每隔一段时间生成一个崭新页面。当服务器产生一个崭新页面（对于缓存过期后的第一个用户访问），它这样做要快得多，因为它的请求并没有超载。
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你可以缓存运行在 LAMP 架构或者 [LEMP 架构][15] 上 WordPress 的动态文件（在 [技巧 3][16] 中说明了）。有几个缓存插件，你可以在 WordPress 中使用。这里有最流行的缓存插件和缓存技术，从最简单到最强大的：
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你可以缓存运行在 LAMP 架构或者 [LEMP 架构][15] 上 WordPress 的动态文件（在 [技巧 3][16] 中说明了）。有几个缓存插件，你可以在 WordPress 中使用。运用到了最流行的缓存插件和缓存技术，从最简单到最强大的：
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- [Hyper-Cache][17] 和 [Quick-Cache][18] – 这两个插件为每个 WordPress 页面创建单个 PHP 文件。它支持的一些动态函数会绕过多个 WordPress 与数据库的连接核心处理，创建一个更快的用户体验。他们不会绕过所有的 PHP 处理，所以使用以下选项他们不能给出相同的性能提升。他们也不需要修改 NGINX 的配置。
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- [Hyper-Cache][17] 和 [Quick-Cache][18] – 这两个插件为每个 WordPress 页面创建单个 PHP 文件。它支持绕过多个 WordPress 与数据库的连接核心处理的一些动态功能，创建一个更快的用户体验。它们不会绕过所有的 PHP 处理，所以并不会如下面那些取得同样的性能提升。它们也不需要修改 NGINX 的配置。
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- [WP Super Cache][19] – 最流行的 WordPress 缓存插件。它有许多功能，它的界面非常简洁，如下图所示。我们展示了 NGINX 一个简单的配置实例在 [技巧 7][20] 中。
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- [WP Super Cache][19] – 最流行的 WordPress 缓存插件。在它易用的界面易用上提供了许多功能，如下所示。我们在 [技巧 7][20] 中展示了一个简单的 NGINX 配置实例。
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- [W3 Total Cache][21] – 这是第二大最受欢迎的 WordPress 缓存插件。它比 WP Super Cache 的功能更强大，但它有些配置选项比较复杂。一个 NGINX 的简单配置，请看 [技巧 6][22]。
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- [W3 Total Cache][21] – 这是第二流行的 WordPress 缓存插件。它比 WP Super Cache 的功能更强大，但它有些配置选项比较复杂。样例 NGINX 配置，请看 [技巧 6][22]。
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- [FastCGI][23] – CGI 代表通用网关接口，在因特网上发送请求和接收文件。它不是一个插件只是一种能直接使用缓存的方法。FastCGI 可以被用在 Apache 和 Nginx 上，它也是最流行的动态缓存方法；我们在 [技巧 5][24] 中描述了如何配置 NGINX 来使用它。
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- [FastCGI][23] – CGI 的意思是通用网关接口（ Common Gateway Interface），在因特网上发送请求和接收文件的一种通用方式。它不是一个插件，而是一种与缓存交互缓存的方法。FastCGI 可以被用在 Apache 和 Nginx 上，它也是最流行的动态缓存方法；我们在 [技巧 5][24] 中描述了如何配置 NGINX 来使用它。
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这些插件的技术文档解释了如何在 LAMP 架构中配置它们。配置选项包括数据库和对象缓存；也包括使用 HTML，CSS 和 JavaScript 来构建 CDN 集成环境。对于 NGINX 的配置，请看列表中的提示技巧。
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这些插件和技术的文档解释了如何在典型的 LAMP 架构中配置它们。配置方式包括数据库和对象缓存；最小化 HTML、CSS 和 JavaScript；集成流行的 CDN 集成环境。对于 NGINX 的配置，请看列表中的提示技巧。
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**注意**：WordPress 不能缓存用户的登录信息，因为它们的 WordPress 页面都是不同的。（对于大多数网站来说，只有一小部分用户可能会登录），大多数缓存不会对刚刚评论过的用户显示缓存页面，只有当用户刷新页面时才会看到他们的评论。若要缓存页面的非个性化内容，如果它对整体性能来说很重要，可以使用一种称为 [fragment caching][25] 的技术。
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**注意**：缓存不会用于已经登录的 WordPress 用户，因为他们的 WordPress 页面都是不同的。（对于大多数网站来说，只有一小部分用户可能会登录）此外，大多数缓存不会对刚刚评论过的用户显示缓存页面，因为当用户刷新页面时希望看到他们的评论。若要缓存页面的非个性化内容，如果它对整体性能来说很重要，可以使用一种称为 [碎片缓存（fragment caching）][25] 的技术。
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### 技巧 3. 使用 NGINX ###
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||||
|
||||
如上所述，当并发用户数超过某一值时 Apache 会导致性能问题 – 可能数百个用户同时使用。Apache 对于每一个连接会消耗大量的资源，因而容易耗尽内存。Apache 可以配置连接数的值来避免耗尽内存，但是这意味着，超过限制时，新的连接请求必须等待。
|
||||
如上所述，当并发用户数超过某一数量时 Apache 会导致性能问题 – 可能是数百个用户同时使用。Apache 对于每一个连接会消耗大量的资源，因而容易耗尽内存。Apache 可以配置连接数的值来避免耗尽内存，但是这意味着，超过限制时，新的连接请求必须等待。
|
||||
|
||||
此外，Apache 使用 mod_php 模块将每一个连接加载到内存中，即使只有静态文件（图片，CSS，JavaScript 等）。这使得每个连接消耗更多的资源，从而限制了服务器的性能。
|
||||
此外，Apache 为每个连接加载一个 mod_php 模块副本到内存中，即使只有服务于静态文件（图片，CSS，JavaScript 等）。这使得每个连接消耗更多的资源，从而限制了服务器的性能。
|
||||
|
||||
开始解决这些问题吧，从 LAMP 架构迁到 LEMP 架构 – 使用 NGINX 取代 Apache 。NGINX 仅消耗很少量的内存就能处理成千上万的并发连接数，所以你不必经历颠簸，也不必限制并发连接数。
|
||||
要解决这些问题，从 LAMP 架构迁到 LEMP 架构 – 使用 NGINX 取代 Apache 。NGINX 在一定的内存之下就能处理成千上万的并发连接数，所以你不必经历颠簸，也不必限制并发连接数到很小的数量。
|
||||
|
||||
NGINX 处理静态文件的性能也较好，它有内置的，简单的 [缓存][26] 控制策略。减少应用服务器的负载，你的网站的访问速度会更快，用户体验更好。
|
||||
NGINX 处理静态文件的性能也较好，它有内置的，容易调整的 [缓存][26] 控制策略。减少应用服务器的负载，你的网站的访问速度会更快，用户体验更好。
|
||||
|
||||
你可以在部署的所有 Web 服务器上使用 NGINX，或者你可以把一个 NGINX 服务器作为 Apache 的“前端”来进行反向代理 - NGINX 服务器接收客户端请求，将请求的静态文件直接返回，将 PHP 请求转发到 Apache 上进行处理。
|
||||
你可以在部署环境的所有 Web 服务器上使用 NGINX，或者你可以把一个 NGINX 服务器作为 Apache 的“前端”来进行反向代理 - NGINX 服务器接收客户端请求，将请求的静态文件直接返回，将 PHP 请求转发到 Apache 上进行处理。
|
||||
|
||||
对于动态页面的生成 - WordPress 核心体验 - 选择一个缓存工具，如 [技巧 2][27] 中描述的。在下面的技巧中，你可以看到 FastCGI，W3_Total_Cache 和 WP-Super-Cache 在 NGINX 上的配置示例。 （Hyper-Cache 和 Quick-Cache 不需要改变 NGINX 的配置。）
|
||||
对于动态页面的生成，这是 WordPress 核心体验，可以选择一个缓存工具，如 [技巧 2][27] 中描述的。在下面的技巧中，你可以看到 FastCGI，W3\_Total\_Cache 和 WP-Super-Cache 在 NGINX 上的配置示例。 （Hyper-Cache 和 Quick-Cache 不需要改变 NGINX 的配置。）
|
||||
|
||||
**技巧** 缓存通常会被保存到磁盘上，但你可以用 [tmpfs][28] 将缓存放在内存中来提高性能。
|
||||
|
||||
为 WordPress 配置 NGINX 很容易。按照这四个步骤，其详细的描述在指定的技巧中：
|
||||
为 WordPress 配置 NGINX 很容易。仅需四步，其详细的描述在指定的技巧中：
|
||||
|
||||
1.添加永久的支持 - 添加对 NGINX 的永久支持。此步消除了对 **.htaccess** 配置文件的依赖，这是 Apache 特有的。参见 [技巧 4][29]
|
||||
2.配置缓存 - 选择一个缓存工具并安装好它。可选择的有 FastCGI cache，W3 Total Cache, WP Super Cache, Hyper Cache, 和 Quick Cache。请看技巧 [5][30], [6][31], 和 [7][32].
|
||||
3.落实安全防范措施 - 在 NGINX 上采用对 WordPress 最佳安全的做法。参见 [技巧 8][33]。
|
||||
4.配置 WordPress 多站点 - 如果你使用 WordPress 多站点，在 NGINX 下配置子目录，子域，或多个域的结构。见 [技巧9][34]。
|
||||
1. 添加永久链接的支持 - 让 NGINX 支持永久链接。此步消除了对 **.htaccess** 配置文件的依赖，这是 Apache 特有的。参见 [技巧 4][29]。
|
||||
2. 配置缓存 - 选择一个缓存工具并安装好它。可选择的有 FastCGI cache，W3 Total Cache, WP Super Cache, Hyper Cache, 和 Quick Cache。请看技巧 [5][30]、 [6][31] 和 [7][32]。
|
||||
3. 落实安全防范措施 - 在 NGINX 上采用对 WordPress 最佳安全的做法。参见 [技巧 8][33]。
|
||||
4. 配置 WordPress 多站点 - 如果你使用 WordPress 多站点，在 NGINX 下配置子目录，子域，或多域名架构。见 [技巧9][34]。
|
||||
|
||||
### 技巧 4. 添加支持 NGINX 的链接 ###
|
||||
### 技巧 4. 让 NGINX 支持永久链接 ###
|
||||
|
||||
许多 WordPress 网站依靠 **.htaccess** 文件，此文件依赖 WordPress 的多个功能，包括永久支持，插件和文件缓存。NGINX 不支持 **.htaccess** 文件。幸运的是，你可以使用 NGINX 的简单而全面的配置文件来实现大部分相同的功能。
|
||||
许多 WordPress 网站依赖于 **.htaccess** 文件，此文件为 WordPress 的多个功能所需要，包括永久链接支持、插件和文件缓存。NGINX 不支持 **.htaccess** 文件。幸运的是，你可以使用 NGINX 的简单而全面的配置文件来实现大部分相同的功能。
|
||||
|
||||
你可以在使用 NGINX 的 WordPress 中通过在主 [server][36] 块下添加下面的 location 块中启用 [永久链接][35]。（此 location 块在其他代码示例中也会被包括）。
|
||||
你可以在你的主 [server][36] 块下添加下面的 location 块中为使用 NGINX 的 WordPress 启用 [永久链接][35]。（此 location 块在其它代码示例中也会被包括）。
|
||||
|
||||
**try_files** 指令告诉 NGINX 检查请求的 URL 在根目录下是作为文件(**$uri**)还是目录(**$uri/**)，**/var/www/example.com/htdocs**。如果都不是，NGINX 将重定向到 **/index.php**，通过查询字符串参数判断是否作为参数。
|
||||
**try_files** 指令告诉 NGINX 检查请求的 URL 在文档根目录（**/var/www/example.com/htdocs**）下是作为文件(**$uri**)还是目录(**$uri/**) 存在的。如果都不是，NGINX 将重定向到 **/index.php**，并传递查询字符串参数作为参数。
|
||||
|
||||
server {
|
||||
server_name example.com www.example.com;
|
||||
@ -159,17 +158,17 @@ NGINX 处理静态文件的性能也较好，它有内置的，简单的 [缓存
|
||||
|
||||
### 技巧 5. 在 NGINX 中配置 FastCGI ###
|
||||
|
||||
NGINX 可以从 FastCGI 应用程序中缓存响应，如 PHP 响应。此方法可提供最佳的性能。
|
||||
NGINX 可以缓存来自 FastCGI 应用程序的响应，如 PHP 响应。此方法可提供最佳的性能。
|
||||
|
||||
对于开源的 NGINX，第三方模块 [ngx_cache_purge][37] 提供了缓存清除能力，需要手动编译，配置代码如下所示。NGINX Plus 已经包含了此代码的实现。
|
||||
对于开源的 NGINX，编译入第三方模块 [ngx\_cache\_purge][37] 可以提供缓存清除能力，配置代码如下所示。NGINX Plus 已经包含了它自己实现此代码。
|
||||
|
||||
当使用 FastCGI 时，我们建议你安装 [NGINX 辅助插件][38] 并使用下面的配置文件，尤其是要使用 **fastcgi_cache_key** 并且 location 块下要包括 **fastcgi_cache_purge**。当页面被发布或有改变时，甚至有新评论被发布时，该插件会自动清除你的缓存，你也可以从 WordPress 管理控制台手动清除。
|
||||
当使用 FastCGI 时，我们建议你安装 [NGINX 辅助插件][38] 并使用下面的配置文件，尤其是要注意 **fastcgi\_cache\_key** 的使用和包括 **fastcgi\_cache\_purge** 的 location 块。当页面发布或有改变时，有新评论被发布时，该插件会自动清除你的缓存，你也可以从 WordPress 管理控制台手动清除。
|
||||
|
||||
NGINX 的辅助插件还可以添加一个简短的 HTML 代码到你网页的底部，确认缓存是否正常并显示一些统计工作。（你也可以使用 [$upstream_cache_status][39] 确认缓存功能是否正常。）
|
||||
NGINX 的辅助插件还可以在你网页的底部添加一个简短的 HTML 代码，以确认缓存是否正常并显示一些统计数据。（你也可以使用 [$upstream\_cache\_status][39] 确认缓存功能是否正常。）
|
||||
|
||||
fastcgi_cache_path /var/run/nginx-cache levels=1:2
|
||||
fastcgi_cache_path /var/run/nginx-cache levels=1:2
|
||||
keys_zone=WORDPRESS:100m inactive=60m;
|
||||
fastcgi_cache_key "$scheme$request_method$host$request_uri";
|
||||
fastcgi_cache_key "$scheme$request_method$host$request_uri";
|
||||
|
||||
server {
|
||||
server_name example.com www.example.com;
|
||||
@ -181,7 +180,7 @@ fastcgi_cache_key "$scheme$request_method$host$request_uri";
|
||||
|
||||
set $skip_cache 0;
|
||||
|
||||
# POST 请求和查询网址的字符串应该交给 PHP
|
||||
# POST 请求和带有查询参数的网址应该交给 PHP
|
||||
if ($request_method = POST) {
|
||||
set $skip_cache 1;
|
||||
}
|
||||
@ -196,7 +195,7 @@ fastcgi_cache_key "$scheme$request_method$host$request_uri";
|
||||
set $skip_cache 1;
|
||||
}
|
||||
|
||||
#用户不能使用缓存登录或缓存最近的评论
|
||||
#不要为登录用户或最近的评论者进行缓存
|
||||
if ($http_cookie ~* "comment_author|wordpress_[a-f0-9]+|wp-postpass
|
||||
|wordpress_no_cache|wordpress_logged_in") {
|
||||
set $skip_cache 1;
|
||||
@ -240,13 +239,13 @@ fastcgi_cache_key "$scheme$request_method$host$request_uri";
|
||||
}
|
||||
}
|
||||
|
||||
### 技巧 6. 为 NGINX 配置 W3_Total_Cache ###
|
||||
### 技巧 6. 为 NGINX 配置 W3\_Total\_Cache ###
|
||||
|
||||
[W3 Total Cache][40], 是 Frederick Townes 的 [W3-Edge][41] 下的, 是一个支持 NGINX 的 WordPress 缓存框架。其有众多选项配置，可以替代 FastCGI 缓存。
|
||||
[W3 Total Cache][40], 是 [W3-Edge][41] 的 Frederick Townes 出品的， 是一个支持 NGINX 的 WordPress 缓存框架。其有众多选项配置，可以替代 FastCGI 缓存。
|
||||
|
||||
缓存插件提供了各种缓存配置，还包括数据库和对象的缓存，对 HTML，CSS 和 JavaScript，可选择性的与流行的 CDN 整合。
|
||||
这个缓存插件提供了各种缓存配置，还包括数据库和对象的缓存，最小化 HTML、CSS 和 JavaScript，并可选与流行的 CDN 整合。
|
||||
|
||||
使用插件时，需要将其配置信息写入位于你的域的根目录的 NGINX 配置文件中。
|
||||
这个插件会通过写入一个位于你的域的根目录的 NGINX 配置文件来控制 NGINX。
|
||||
|
||||
server {
|
||||
server_name example.com www.example.com;
|
||||
@ -271,11 +270,11 @@ fastcgi_cache_key "$scheme$request_method$host$request_uri";
|
||||
|
||||
### 技巧 7. 为 NGINX 配置 WP Super Cache ###
|
||||
|
||||
[WP Super Cache][42] 是由 Donncha O Caoimh 完成的, [Automattic][43] 上的一个 WordPress 开发者, 这是一个 WordPress 缓存引擎，它可以将 WordPress 的动态页面转变成静态 HTML 文件，以使 NGINX 可以很快的提供服务。它是第一个 WordPress 缓存插件，和其他的相比，它更专注于某一特定的领域。
|
||||
[WP Super Cache][42] 是由 Donncha O Caoimh 开发的, 他是 [Automattic][43] 的一个 WordPress 开发者, 这是一个 WordPress 缓存引擎，它可以将 WordPress 的动态页面转变成静态 HTML 文件，以使 NGINX 可以很快的提供服务。它是第一个 WordPress 缓存插件，和其它的相比，它更专注于某一特定的领域。
|
||||
|
||||
配置 NGINX 使用 WP Super Cache 可以根据你的喜好而进行不同的配置。以下是一个示例配置。
|
||||
|
||||
在下面的配置中，location 块中使用了名为 WP Super Cache 的超级缓存中部分配置来工作。代码的其余部分是根据 WordPress 的规则不缓存用户登录信息，不缓存 POST 请求，并对静态资源设置过期首部，再加上标准的 PHP 实现;这部分可以进行定制，来满足你的需求。
|
||||
在下面的配置中，带有名为 supercache 的 location 块是 WP Super Cache 特有的部分。 WordPress 规则的其余代码用于不缓存已登录用户的信息，不缓存 POST 请求，并对静态资源设置过期首部，再加上标准的 PHP 处理；这部分可以根据你的需求进行定制。
|
||||
|
||||
|
||||
server {
|
||||
@ -288,7 +287,7 @@ fastcgi_cache_key "$scheme$request_method$host$request_uri";
|
||||
|
||||
set $cache_uri $request_uri;
|
||||
|
||||
# POST 请求和查询网址的字符串应该交给 PHP
|
||||
# POST 请求和带有查询字符串的网址应该交给 PHP
|
||||
if ($request_method = POST) {
|
||||
set $cache_uri 'null cache';
|
||||
}
|
||||
@ -305,13 +304,13 @@ fastcgi_cache_key "$scheme$request_method$host$request_uri";
|
||||
set $cache_uri 'null cache';
|
||||
}
|
||||
|
||||
#用户不能使用缓存登录或缓存最近的评论
|
||||
#不对已登录用户和最近的评论者使用缓存
|
||||
if ($http_cookie ~* "comment_author|wordpress_[a-f0-9]+
|
||||
|wp-postpass|wordpress_logged_in") {
|
||||
set $cache_uri 'null cache';
|
||||
}
|
||||
|
||||
#当请求的文件存在时使用缓存，否则将请求转发给WordPress
|
||||
#当请求的文件存在时使用缓存，否则将请求转发给 WordPress
|
||||
location / {
|
||||
try_files /wp-content/cache/supercache/$http_host/$cache_uri/index.html
|
||||
$uri $uri/ /index.php;
|
||||
@ -346,7 +345,7 @@ fastcgi_cache_key "$scheme$request_method$host$request_uri";
|
||||
|
||||
### 技巧 8. 为 NGINX 配置安全防范措施 ###
|
||||
|
||||
为了防止攻击，可以控制对关键资源的访问以及当机器超载时进行登录限制。
|
||||
为了防止攻击，可以控制对关键资源的访问并限制机器人对登录功能的过量攻击。
|
||||
|
||||
只允许特定的 IP 地址访问 WordPress 的仪表盘。
|
||||
|
||||
@ -365,14 +364,14 @@ fastcgi_cache_key "$scheme$request_method$host$request_uri";
|
||||
deny all;
|
||||
}
|
||||
|
||||
拒绝其他人访问 WordPress 的配置文件 **wp-config.php**。拒绝其他人访问的另一种方法是将该文件的一个目录移到域的根目录下。
|
||||
拒绝其它人访问 WordPress 的配置文件 **wp-config.php**。拒绝其它人访问的另一种方法是将该文件的一个目录移到域的根目录之上的目录。
|
||||
|
||||
# 拒绝其他人访问 wp-config.php
|
||||
# 拒绝其它人访问 wp-config.php
|
||||
location ~* wp-config.php {
|
||||
deny all;
|
||||
}
|
||||
|
||||
对 **wp-login.php** 进行限速来防止暴力攻击。
|
||||
对 **wp-login.php** 进行限速来防止暴力破解。
|
||||
|
||||
# 拒绝访问 wp-login.php
|
||||
location = /wp-login.php {
|
||||
@ -383,27 +382,27 @@ fastcgi_cache_key "$scheme$request_method$host$request_uri";
|
||||
|
||||
### 技巧 9. 配置 NGINX 支持 WordPress 多站点 ###
|
||||
|
||||
WordPress 多站点，顾名思义，使用同一个版本的 WordPress 从单个实例中允许你管理两个或多个网站。[WordPress.com][44] 运行的就是 WordPress 多站点，其主机为成千上万的用户提供博客服务。
|
||||
WordPress 多站点（WordPress Multisite），顾名思义，这个版本 WordPress 可以让你以单个实例管理两个或多个网站。[WordPress.com][44] 运行的就是 WordPress 多站点，其主机为成千上万的用户提供博客服务。
|
||||
|
||||
你可以从单个域的任何子目录或从不同的子域来运行独立的网站。
|
||||
|
||||
使用此代码块添加对子目录的支持。
|
||||
|
||||
# 在 WordPress 中添加支持子目录结构的多站点
|
||||
# 在 WordPress 多站点中添加对子目录结构的支持
|
||||
if (!-e $request_filename) {
|
||||
rewrite /wp-admin$ $scheme://$host$uri/ permanent;
|
||||
rewrite ^(/[^/]+)?(/wp-.*) $2 last;
|
||||
rewrite ^(/[^/]+)?(/.*\.php) $2 last;
|
||||
}
|
||||
|
||||
使用此代码块来替换上面的代码块以添加对子目录结构的支持，子目录名自定义。
|
||||
使用此代码块来替换上面的代码块以添加对子目录结构的支持，替换为你自己的子目录名。
|
||||
|
||||
# 添加支持子域名
|
||||
server_name example.com *.example.com;
|
||||
|
||||
旧版本（3.4以前）的 WordPress 多站点使用 readfile() 来提供静态内容。然而，readfile() 是 PHP 代码，它会导致在执行时性能会显著降低。我们可以用 NGINX 来绕过这个非必要的 PHP 处理。该代码片段在下面被（==============）线分割出来了。
|
||||
|
||||
# 避免 PHP readfile() 在 /blogs.dir/structure 子目录中
|
||||
# 避免对子目录中 /blogs.dir/ 结构执行 PHP readfile()
|
||||
location ^~ /blogs.dir {
|
||||
internal;
|
||||
alias /var/www/example.com/htdocs/wp-content/blogs.dir;
|
||||
@ -414,8 +413,8 @@ WordPress 多站点，顾名思义，使用同一个版本的 WordPress 从单
|
||||
|
||||
============================================================
|
||||
|
||||
# 避免 PHP readfile() 在 /files/structure 子目录中
|
||||
location ~ ^(/[^/]+/)?files/(?.+) {
|
||||
# 避免对子目录中 /files/ 结构执行 PHP readfile()
|
||||
location ~ ^(/[^/]+/)?files/(?.+) {
|
||||
try_files /wp-content/blogs.dir/$blogid/files/$rt_file /wp-includes/ms-files.php?file=$rt_file;
|
||||
access_log off;
|
||||
log_not_found off;
|
||||
@ -424,7 +423,7 @@ WordPress 多站点，顾名思义，使用同一个版本的 WordPress 从单
|
||||
|
||||
============================================================
|
||||
|
||||
# WPMU 文件结构的子域路径
|
||||
# 子域路径的WPMU 文件结构
|
||||
location ~ ^/files/(.*)$ {
|
||||
try_files /wp-includes/ms-files.php?file=$1 =404;
|
||||
access_log off;
|
||||
@ -434,7 +433,7 @@ WordPress 多站点，顾名思义，使用同一个版本的 WordPress 从单
|
||||
|
||||
============================================================
|
||||
|
||||
# 地图博客 ID 在特定的目录下
|
||||
# 映射博客 ID 到特定的目录
|
||||
map $http_host $blogid {
|
||||
default 0;
|
||||
example.com 1;
|
||||
@ -444,15 +443,15 @@ WordPress 多站点，顾名思义，使用同一个版本的 WordPress 从单
|
||||
|
||||
### 结论 ###
|
||||
|
||||
可扩展性对许多站点的开发者来说是一项挑战，因为这会让他们在 WordPress 站点中取得成功。（对于那些想要跨越 WordPress 性能问题的新站点。）为 WordPress 添加缓存，并将 WordPress 和 NGINX 结合，是不错的答案。
|
||||
可扩展性对许多要让他们的 WordPress 站点取得成功的开发者来说是一项挑战。（对于那些想要跨越 WordPress 性能门槛的新站点而言。）为 WordPress 添加缓存，并将 WordPress 和 NGINX 结合，是不错的答案。
|
||||
|
||||
NGINX 不仅对 WordPress 网站是有用的。世界上排名前 1000，10,000和100,000网站中 NGINX 也是作为 [领先的 web 服务器][45] 被使用。
|
||||
NGINX 不仅用于 WordPress 网站。世界上排名前 1000、10000 和 100000 网站中 NGINX 也是 [遥遥领先的 web 服务器][45]。
|
||||
|
||||
欲了解更多有关 NGINX 的性能，请看我们最近的博客，[关于 10x 应用程序的 10 个技巧][46]。
|
||||
欲了解更多有关 NGINX 的性能，请看我们最近的博客，[让应用性能提升 10 倍的 10 个技巧][46]。
|
||||
|
||||
NGINX 软件有两个版本：
|
||||
|
||||
- NGINX 开源的软件 - 像 WordPress 一样，此软件你可以自行下载，配置和编译。
|
||||
- NGINX 开源软件 - 像 WordPress 一样，此软件你可以自行下载，配置和编译。
|
||||
- NGINX Plus - NGINX Plus 包括一个预构建的参考版本的软件，以及服务和技术支持。
|
||||
|
||||
想要开始，先到 [nginx.org][47] 下载开源软件并了解下 [NGINX Plus][48]。
|
||||
@ -463,7 +462,7 @@ via: https://www.nginx.com/blog/9-tips-for-improving-wordpress-performance-with-
|
||||
|
||||
作者：[Floyd Smith][a]
|
||||
译者：[strugglingyouth](https://github.com/strugglingyouth)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -1,14 +1,14 @@
|
||||
在 Ubuntu 15.10 上安装 PostgreSQL 9.4 和 phpPgAdmin
|
||||
在 Ubuntu 上安装世界上最先进的开源数据库 PostgreSQL 9.4 和 phpPgAdmin
|
||||
================================================================================
|
||||
|
||||
|
||||
### 简介 ###
|
||||
|
||||
[PostgreSQL][1] 是一款强大的，开源对象关系型数据库系统。它支持所有的主流操作系统，包括 Linux、Unix（AIX、BSD、HP-UX，SGI IRIX、Mac OS、Solaris、Tru64） 以及 Windows 操作系统。
|
||||
[PostgreSQL][1] 是一款强大的，开源的，对象关系型数据库系统。它支持所有的主流操作系统，包括 Linux、Unix（AIX、BSD、HP-UX，SGI IRIX、Mac OS、Solaris、Tru64） 以及 Windows 操作系统。
|
||||
|
||||
下面是 **Ubuntu** 发起者 **Mark Shuttleworth** 对 PostgreSQL 的一段评价。
|
||||
|
||||
> PostgreSQL 真的是一款很好的数据库系统。刚开始我们使用它的时候，并不确定它能否胜任工作。但我错的太离谱了。它很强壮、快速，在各个方面都很专业。
|
||||
> PostgreSQL 是一款极赞的数据库系统。刚开始我们在 Launchpad 上使用它的时候，并不确定它能否胜任工作。但我是错了。它很强壮、快速，在各个方面都很专业。
|
||||
>
|
||||
> — Mark Shuttleworth.
|
||||
|
||||
@ -22,7 +22,7 @@
|
||||
|
||||
如果你需要其它的版本，按照下面那样先添加 PostgreSQL 仓库然后再安装。
|
||||
|
||||
**PostgreSQL apt 仓库** 支持 amd64 和 i386 架构的 Ubuntu 长期支持版（10.04、12.04 和 14.04），以及非长期支持版（14.04）。对于其它非长期支持版，该软件包虽然不能完全支持，但使用和 LTS 版本近似的也能正常工作。
|
||||
**PostgreSQL apt 仓库** 支持 amd64 和 i386 架构的 Ubuntu 长期支持版（10.04、12.04 和 14.04），以及非长期支持版（14.04）。对于其它非长期支持版，该软件包虽然没有完全支持，但使用和 LTS 版本近似的也能正常工作。
|
||||
|
||||
#### Ubuntu 14.10 系统： ####
|
||||
|
||||
@ -36,11 +36,11 @@
|
||||
|
||||
**注意**： 上面的库只能用于 Ubuntu 14.10。还没有升级到 Ubuntu 15.04 和 15.10。
|
||||
|
||||
**Ubuntu 14.04**，添加下面一行：
|
||||
对于 **Ubuntu 14.04**，添加下面一行：
|
||||
|
||||
deb http://apt.postgresql.org/pub/repos/apt/ trusty-pgdg main
|
||||
|
||||
**Ubuntu 12.04**，添加下面一行：
|
||||
对于 **Ubuntu 12.04**，添加下面一行：
|
||||
|
||||
deb http://apt.postgresql.org/pub/repos/apt/ precise-pgdg main
|
||||
|
||||
@ -48,8 +48,6 @@
|
||||
|
||||
wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc
|
||||
|
||||
----------
|
||||
|
||||
sudo apt-key add -
|
||||
|
||||
更新软件包列表：
|
||||
@ -66,7 +64,7 @@
|
||||
|
||||
sudo -u postgres psql postgres
|
||||
|
||||
#### 事例输出： ####
|
||||
#### 示例输出： ####
|
||||
|
||||
psql (9.4.5)
|
||||
Type "help" for help.
|
||||
@ -87,7 +85,7 @@
|
||||
Enter it again:
|
||||
postgres=# \q
|
||||
|
||||
要安装 PostgreSQL Adminpack，在 postgresql 窗口输入下面的命令：
|
||||
要安装 PostgreSQL Adminpack 扩展，在 postgresql 窗口输入下面的命令：
|
||||
|
||||
sudo -u postgres psql postgres
|
||||
|
||||
@ -165,7 +163,7 @@
|
||||
#port = 5432
|
||||
[...]
|
||||
|
||||
取消改行的注释，然后设置你 postgresql 服务器的 IP 地址，或者设置为 ‘*’ 监听所有用户。你应该谨慎设置所有远程用户都可以访问 PostgreSQL。
|
||||
取消该行的注释，然后设置你 postgresql 服务器的 IP 地址，或者设置为 ‘*’ 监听所有用户。你应该谨慎设置所有远程用户都可以访问 PostgreSQL。
|
||||
|
||||
[...]
|
||||
listen_addresses = '*'
|
||||
@ -272,8 +270,6 @@
|
||||
|
||||
sudo systemctl restart postgresql
|
||||
|
||||
----------
|
||||
|
||||
sudo systemctl restart apache2
|
||||
|
||||
或者，
|
||||
@ -284,19 +280,19 @@
|
||||
|
||||
现在打开你的浏览器并导航到 **http://ip-address/phppgadmin**。你会看到以下截图。
|
||||
|
||||
|
||||
|
||||
|
||||
用你之前创建的用户登录。我之前已经创建了一个名为 “**senthil**” 的用户，密码是 “**ubuntu**”，因此我以 “senthil” 用户登录。
|
||||
|
||||
|
||||
|
||||
|
||||
然后你就可以访问 phppgadmin 面板了。
|
||||
|
||||
|
||||
|
||||
|
||||
用 postgres 用户登录：
|
||||
|
||||
|
||||
|
||||
|
||||
就是这样。现在你可以用 phppgadmin 可视化创建、删除或者更改数据库了。
|
||||
|
||||
@ -308,7 +304,7 @@ via: http://www.unixmen.com/install-postgresql-9-4-and-phppgadmin-on-ubuntu-15-1
|
||||
|
||||
作者：[SK][a]
|
||||
译者：[ictlyh](http://mutouxiaogui.cn/blog/)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -1,11 +1,16 @@
|
||||
|
||||
在 Centos/RHEL 6.X 上安装 Wetty
|
||||
================================================================================
|
||||
|
||||
|
||||
Wetty 是什么?
|
||||
**Wetty 是什么?**
|
||||
|
||||
作为系统管理员，如果你是在 Linux 桌面下，你可能会使用一个软件来连接远程服务器，像 GNOME 终端（或类似的），如果你是在 Windows 下，你可能会使用像 Putty 这样的 SSH 客户端来连接，并同时可以在浏览器中查收邮件等做其他事情。
|
||||
Wetty = Web + tty
|
||||
|
||||
作为系统管理员，如果你是在 Linux 桌面下，你可以用它像一个 GNOME 终端（或类似的）一样来连接远程服务器；如果你是在 Windows 下，你可以用它像使用 Putty 这样的 SSH 客户端一样来连接远程，然后同时可以在浏览器中上网并查收邮件等其它事情。
|
||||
|
||||
（LCTT 译注：简而言之，这是一个基于 Web 浏览器的远程终端）
|
||||
|
||||
|
||||
|
||||
### 第1步: 安装 epel 源 ###
|
||||
|
||||
@ -15,6 +20,8 @@ Wetty 是什么?
|
||||
### 第2步：安装依赖 ###
|
||||
|
||||
# yum install epel-release git nodejs npm -y
|
||||
|
||||
（LCTT 译注：对，没错，是用 node.js 编写的）
|
||||
|
||||
### 第3步：在安装完依赖后，克隆 GitHub 仓库 ###
|
||||
|
||||
@ -31,13 +38,15 @@ Wetty 是什么?
|
||||
|
||||
### 第6步：为 Wetty 安装 HTTPS 证书 ###
|
||||
|
||||
# openssl req -x509 -newkey rsa:2048 -keyout key.pem -out cert.pem -days 365 -nodes (complete this)
|
||||
# openssl req -x509 -newkey rsa:2048 -keyout key.pem -out cert.pem -days 365 -nodes
|
||||
|
||||
(等待完成)
|
||||
|
||||
### Step 7: 通过 HTTPS 来使用 Wetty ###
|
||||
### 第7步：通过 HTTPS 来使用 Wetty ###
|
||||
|
||||
# nohup node app.js --sslkey key.pem --sslcert cert.pem -p 8080 &
|
||||
|
||||
### Step 8: 为 wetty 添加一个用户 ###
|
||||
### 第8步：为 wetty 添加一个用户 ###
|
||||
|
||||
# useradd <username>
|
||||
# Passwd <username>
|
||||
@ -45,7 +54,8 @@ Wetty 是什么?
|
||||
### 第9步：访问 wetty ###
|
||||
|
||||
http://Your_IP-Address:8080
|
||||
give the credential have created before for wetty and access
|
||||
|
||||
输入你之前为 wetty 创建的证书然后访问。
|
||||
|
||||
到此结束！
|
||||
|
||||
@ -55,7 +65,7 @@ via: http://www.unixmen.com/install-wetty-centosrhel-6-x/
|
||||
|
||||
作者：[Debojyoti Das][a]
|
||||
译者：[strugglingyouth](https://github.com/strugglingyouth)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -1,220 +0,0 @@
|
||||
19 Years of KDE History: Step by Step
|
||||
================================================================================
|
||||
注：youtube 视频
|
||||
<iframe width="660" height="371" src="https://www.youtube.com/embed/1UG4lQOMBC4?feature=oembed" frameborder="0" allowfullscreen></iframe>
|
||||
|
||||
### Introduction ###
|
||||
|
||||
KDE – one of most functional desktop environment ever. It’s open source and free for use. 19 years ago, 14 october 1996 german programmer Matthias Ettrich has started a development of this beautiful environment. KDE provides the shell and many applications for everyday using. Today KDE uses the hundred thousand peoples over the world on Unix and Windows operating system. 19 years – serious age for software projects. Time to return and see how it begin.
|
||||
|
||||
K Desktop Environment has some new aspects: new design, good look & feel, consistency, easy to use, powerful applications for typical desktop work and special use cases. Name “KDE” is an easy word hack with “Common Desktop Environment”, “K” – “Cool”. The first KDE version used proprietary Trolltech’s Qt framework (parent of Qt) with dual licensing: open source QPL(Q public license) and proprietary commercial license. In 2000 Trolltech released some Qt libraries under GPL; Qt 4.5 was released in LGPL 2.1. Since 2009 KDE is compiled for three products: Plasma Workspaces (Shell), KDE Applications, KDE Platform as KDE Software compilation.
|
||||
|
||||
### Releases ###
|
||||
|
||||
#### Pre-Release – 14 October 1996 ####
|
||||
|
||||
|
||||
|
||||
Kool Desktop Environment. Word “Kool” will be dropped in future. In the beginning, all components were released to the developer community separately without any coordinated timeframe throughout the overall project. First communication of KDE via mailing list, that was called kde@fiwi02.wiwi.uni-Tubingen.de.
|
||||
|
||||
#### KDE 1.0 – July 12, 1998 ####
|
||||
|
||||
|
||||
|
||||
This version received mixed reception. Many criticized the use of the Qt software framework – back then under the FreeQt license which was claimed to not be compatible with free software – and advised the use of Motif or LessTif instead. Despite that criticism, KDE was well received by many users and made its way into the first Linux distributions.
|
||||
|
||||
|
||||
|
||||
28 January 1999
|
||||
|
||||
An update, **K Desktop Environment 1.1**, was faster, more stable and included many small improvements. It also included a new set of icons, backgrounds and textures. Among this overhauled artwork was a new KDE logo by Torsten Rahn consisting of the letter K in front of a gear which is used in revised form to this day.
|
||||
|
||||
#### KDE 2.0 – October 23, 2000 ####
|
||||
|
||||
|
||||
|
||||
Major updates: * DCOP (Desktop COmmunication Protocol), a client-to-client communications protocol * KIO, an application I/O library. * KParts, a component object model * KHTML, an HTML 4.0 compliant rendering and drawing engine
|
||||
|
||||
|
||||
|
||||
26 February 2001
|
||||
|
||||
**K Desktop Environment 2.1** release inaugurated the media player noatun, which used a modular, plugin design. For development, K Desktop Environment 2.1 was bundled with KDevelop.
|
||||
|
||||
|
||||
|
||||
15 August 2001
|
||||
|
||||
The **KDE 2.2** release featured up to a 50% improvement in application startup time on GNU/Linux systems and increased stability and capabilities for HTML rendering and JavaScript; some new features in KMail.
|
||||
|
||||
#### KDE 3.0 – April 3, 2002 ####
|
||||
|
||||
|
||||
|
||||
K Desktop Environment 3.0 introduced better support for restricted usage, a feature demanded by certain environments such as kiosks, Internet cafes and enterprise deployments, which disallows the user from having full access to all capabilities of a piece of software.
|
||||
|
||||
|
||||
|
||||
28 January 2003
|
||||
|
||||
**K Desktop Environment 3.1** introduced new default window (Keramik) and icon (Crystal) styles as well as several feature enhancements.
|
||||
|
||||
|
||||
|
||||
3 February 2004
|
||||
|
||||
**K Desktop Environment 3.2** included new features, such as inline spell checking for web forms and emails, improved e-mail and calendaring support, tabs in Konqueror and support for Microsoft Windows desktop sharing protocol (RDP).
|
||||
|
||||
|
||||
|
||||
19 August 2004
|
||||
|
||||
**K Desktop Environment 3.3** focused on integrating different desktop components. Kontact was integrated with Kolab, a groupware application, and Kpilot. Konqueror was given better support for instant messaging contacts, with the capability to send files to IM contacts and support for IM protocols (e.g., IRC).
|
||||
|
||||
|
||||
|
||||
16 March 2005
|
||||
|
||||
**K Desktop Environment 3.4** focused on improving accessibility. The update added a text-to-speech system with support for Konqueror, Kate, KPDF, the standalone application KSayIt and text-to-speech synthesis on the desktop.
|
||||
|
||||
|
||||
|
||||
29 November 2005
|
||||
|
||||
**The K Desktop Environment 3.5** release added SuperKaramba, which provides integrated and simple-to-install widgets to the desktop. Konqueror was given an ad-block feature and became the second web browser to pass the Acid2 CSS test.
|
||||
|
||||
#### KDE SC 4.0 – January 11, 2008 ####
|
||||
|
||||
|
||||
|
||||
The majority of development went into implementing most of the new technologies and frameworks of KDE 4. Plasma and the Oxygen style were two of the biggest user-facing changes. Dolphin replaces Konqueror as file manager, Okular – default document viewer.
|
||||
|
||||
|
||||
|
||||
29 July 2008
|
||||
|
||||
**KDE 4.1** includes a shared emoticon theming system which is used in PIM and Kopete, and DXS, a service that lets applications download and install data from the Internet with one click. Also introduced are GStreamer, QuickTime 7, and DirectShow 9 Phonon backends. New applications: * Dragon Player * Kontact * Skanlite – software for scanners * Step – physics simulator * New games: Kdiamond, Kollision, KBreakout and others
|
||||
|
||||
|
||||
|
||||
27 January 2009
|
||||
|
||||
**KDE 4.2** is considered a significant improvement beyond KDE 4.1 in nearly all aspects, and a suitable replacement for KDE 3.5 for most users.
|
||||
|
||||
|
||||
|
||||
4 August 2009
|
||||
|
||||
**KDE 4.3** fixed over 10,000 bugs and implemented almost 2,000 feature requests. Integration with other technologies, such as PolicyKit, NetworkManager & Geolocation services, was another focus of this release.
|
||||
|
||||
|
||||
|
||||
9 February 2010
|
||||
|
||||
**KDE SC 4.4** is based on version 4.6 of the Qt 4 toolkit. New application – KAddressBook, first release of Kopete.
|
||||
|
||||
|
||||
|
||||
10 August 2010
|
||||
|
||||
**KDE SC 4.5** has some new features: integration of the WebKit library, an open-source web browser engine, which is used in major browsers such as Apple Safari and Google Chrome. KPackageKit replaced Kpackage.
|
||||
|
||||
|
||||
|
||||
26 January 2011
|
||||
|
||||
**KDE SC 4.6** has better OpenGL compositing along with the usual myriad of fixes and features.
|
||||
|
||||
|
||||
|
||||
27 July 2011
|
||||
|
||||
**KDE SC 4.7** has updated KWin with OpenGL ES 2.0 compatible, Qt Quick, Plasma Desktop with many enhancements and a lot of new functions in general applications. 12k bugs if fixed.
|
||||
|
||||
|
||||
|
||||
25 January 2012
|
||||
|
||||
**KDE SC 4.8**: better KWin performance and Wayland support, new design of Doplhin.
|
||||
|
||||
|
||||
|
||||
1 August 2012
|
||||
|
||||
**KDE SC 4.9**: several improvements to the Dolphin file manager, including the reintroduction of in-line file renaming, back and forward mouse buttons, improvement of the places panel and better usage of file metadata.
|
||||
|
||||
|
||||
|
||||
6 February 2013
|
||||
|
||||
**KDE SC 4.10**: many of the default Plasma widgets were rewritten in QML, and Nepomuk, Kontact and Okular received significant speed improvements.
|
||||
|
||||
|
||||
|
||||
14 August 2013
|
||||
|
||||
**KDE SC 4.11**: Kontact and Nepomuk received many optimizations. The first generation Plasma Workspaces entered maintenance-only development mode.
|
||||
|
||||
|
||||
|
||||
18 December 2013
|
||||
|
||||
**KDE SC 4.12**: Kontact received substantial improvements, many small improvements.
|
||||
|
||||
|
||||
|
||||
18 December 2013
|
||||
|
||||
**KDE SC 4.13**: Nepomuk semantic desktop search was replaced with KDE’s in house Baloo. KDE SC 4.13 was released in 53 different translations.
|
||||
|
||||
|
||||
|
||||
18 December 2013
|
||||
|
||||
**KDE SC 4.14**: he release primarily focused on stability, with numerous bugs fixed and few new features added. This was the final KDE SC 4 release.
|
||||
|
||||
#### KDE Plasma 5.0 – July 15, 2014 ####
|
||||
|
||||
|
||||
|
||||
KDE Plasma 5 – 5th generation of KDE. Massive impovements in design and system, new default theme – Breeze, complete migration to QML, better performance with OpenGL, better HiDPI displays support.
|
||||
|
||||
|
||||
|
||||
11 November 2014
|
||||
|
||||
**KDE Plasma 5.1**: Ported missing features from Plasma 4.
|
||||
|
||||
|
||||
|
||||
27 January 2015
|
||||
|
||||
**KDE Plasma 5.2**: New components: BlueDevil, KSSHAskPass, Muon, SDDM theme configuration, KScreen, GTK+ style configuration and KDecoration.
|
||||
|
||||
|
||||
|
||||
28 April 2015
|
||||
|
||||
**KDE Plasma 5.3**: Tech preview of Plasma Media Center. New Bluetooth and touchpad applets. Enhanced power management.
|
||||
|
||||
|
||||
|
||||
25 August 2015
|
||||
|
||||
**KDE Plasma 5.4**: Initial Wayland session, new QML-based audio volume applet, and alternative full-screen application launcher.
|
||||
|
||||
Big thanks to the [KDE][1] developers and community, Wikipedia for [descriptions][2] and all my readers. Be free and use the open source software like a KDE.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://tlhp.cf/kde-history/
|
||||
|
||||
作者：[Pavlo RudyiCategories][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://tlhp.cf/author/paul/
|
||||
[1]:https://www.kde.org/
|
||||
[2]:https://en.wikipedia.org/wiki/KDE_Plasma_5
|
||||
@ -1,3 +1,4 @@
|
||||
translation by bestony
|
||||
DFileManager: Cover Flow File Manager
|
||||
================================================================================
|
||||
A real gem of a file manager absent from the standard Ubuntu repositories but sporting a unique feature. That’s DFileManager in a twitterish statement.
|
||||
|
||||
@ -1,3 +1,5 @@
|
||||
taichirain 翻译中
|
||||
|
||||
How to Configure Apache Solr on Ubuntu 14 / 15
|
||||
================================================================================
|
||||
Hello and welcome to our today's article on Apache Solr. The brief description about Apache Solr is that it is an Open Source most famous search platform with Apache Lucene at the back end for Web sites that enables you to easily create search engines which searches websites, databases and files. It can index and search multiple sites and return recommendations for related contents based on the searched text.
|
||||
@ -130,4 +132,4 @@ via: http://linoxide.com/ubuntu-how-to/configure-apache-solr-ubuntu-14-15/
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://linoxide.com/author/kashifs/
|
||||
[1]:http://lucene.apache.org/solr/
|
||||
[1]:http://lucene.apache.org/solr/
|
||||
|
||||
@ -1,3 +1,4 @@
|
||||
Translating by itsang
|
||||
NetworkManager and privacy in the IPv6 internet
|
||||
======================
|
||||
|
||||
|
||||
@ -1,65 +0,0 @@
|
||||
How to Customize Time & Date Format in Ubuntu Panel
|
||||
================================================================================
|
||||
|
||||
|
||||
This quick tutorial is going to show you how to customize your Time & Date indicator in Ubuntu panel, though there are already a few options available in the settings page.
|
||||
|
||||
|
||||
|
||||
To get started, search for and install **dconf Editor** in Ubuntu Software Center. Then launch the software and follow below steps:
|
||||
|
||||
**1.** When dconf Editor launches, navigate to **com -> canonical -> indicator -> datetime**. Set the value of **time-format** to **custom**.
|
||||
|
||||
|
||||
|
||||
You can also do this via a command in terminal:
|
||||
|
||||
gsettings set com.canonical.indicator.datetime time-format 'custom'
|
||||
|
||||
**2.** Now you can customize the Time & Date format by editing the value of **custom-time-format**.
|
||||
|
||||
|
||||
|
||||
You can also do this via command:
|
||||
|
||||
gsettings set com.canonical.indicator.datetime custom-time-format 'FORMAT_VALUE_HERE'
|
||||
|
||||
Interpreted sequences are:
|
||||
|
||||
- %a = abbreviated weekday name
|
||||
- %A = full weekday name
|
||||
- %b = abbreviated month name
|
||||
- %B = full month name
|
||||
- %d = day of month
|
||||
- %l = hour ( 1..12), %I = hour (01..12)
|
||||
- %k = hour ( 1..23), %H = hour (01..23)
|
||||
- %M = minute (00..59)
|
||||
- %p = AM or PM, %P = am or pm.
|
||||
- %S = second (00..59)
|
||||
- open terminal and run command `man date` to get more details.
|
||||
|
||||
Some examples:
|
||||
|
||||
custom time format value: **%a %H:%M %m/%d/%Y**
|
||||
|
||||
|
||||
|
||||
**%a %r %b %d or %a %I:%M:%S %p %b %d**
|
||||
|
||||
|
||||
|
||||
**%a %-d %b %l:%M %P %z**
|
||||
|
||||
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://ubuntuhandbook.org/index.php/2015/12/time-date-format-ubuntu-panel/
|
||||
|
||||
作者：[Ji m][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://ubuntuhandbook.org/index.php/about/
|
||||
@ -1,107 +0,0 @@
|
||||
Translating by bianjp
|
||||
|
||||
How to enable Software Collections (SCL) on CentOS
|
||||
================================================================================
|
||||
Red Hat Enterprise Linux (RHEL) and its community fork, CentOS, offer 10-year life cycle, meaning that each version of RHEL/CentOS is updated with security patches for up to 10 years. While such long life cycle guarantees much needed system compatibility and reliability for enterprise users, a downside is that core applications and run-time environments grow antiquated as the underlying RHEL/CentOS version becomes close to end-of-life (EOF). For example, CentOS 6.5, whose EOL is dated to November 30th 2020, comes with python 2.6.6 and MySQL 5.1.73, which are already pretty old by today's standard.
|
||||
|
||||
On the other hand, attempting to manually upgrade development toolchains and run-time environments on RHEL/CentOS may potentially break your system unless all dependencies are resolved correctly. Under normal circumstances, manual upgrade is not recommended unless you know what you are doing.
|
||||
|
||||
The [Software Collections][1] (SCL) repository came into being to help with RHEL/CentOS users in this situation. The SCL is created to provide RHEL/CentOS users with a means to easily and safely install and use multiple (and potentially more recent) versions of applications and run-time environments "without" messing up the existing system. This is in contrast to other third party repositories which could cause conflicts among installed packages.
|
||||
|
||||
The latest SCL offers:
|
||||
|
||||
- Python 3.3 and 2.7
|
||||
- PHP 5.4
|
||||
- Node.js 0.10
|
||||
- Ruby 1.9.3
|
||||
- Perl 5.16.3
|
||||
- MariaDB and MySQL 5.5
|
||||
- Apache httpd 2.4.6
|
||||
|
||||
In the rest of the tutorial, let me show you how to set up the SCL repository and how to install and enable the packages from the SCL.
|
||||
|
||||
### Set up the Software Collections (SCL) Repository ###
|
||||
|
||||
The SCL is available on CentOS 6.5 and later. To set up the SCL, simply run:
|
||||
|
||||
$ sudo yum install centos-release-SCL
|
||||
|
||||
To enable and run applications from the SCL, you also need to install the following package.
|
||||
|
||||
$ sudo yum install scl-utils-build
|
||||
|
||||
You can browse a complete list of packages available from the SCL repository by running:
|
||||
|
||||
$ yum --disablerepo="*" --enablerepo="scl" list available
|
||||
|
||||
|
||||
|
||||
### Install and Enable a Package from the SCL ###
|
||||
|
||||
Now that you have set up the SCL, you can go ahead and install any package from the SCL.
|
||||
|
||||
You can search for SCL packages with:
|
||||
|
||||
$ yum --disablerepo="*" --enablerepo="scl" search <keyword>
|
||||
|
||||
Let's say you want to install python 3.3.
|
||||
|
||||
Go ahead and install it as usual with yum:
|
||||
|
||||
$ sudo yum install python33
|
||||
|
||||
At any time you can check the list of packages you installed from the SCL by running:
|
||||
|
||||
$ scl --list
|
||||
|
||||
----------
|
||||
|
||||
python33
|
||||
|
||||
A nice thing about the SCL is that installing a package from the SCL does NOT overwrite any system files, and is guaranteed to not cause any conflicts with other system libraries and applications.
|
||||
|
||||
For example, if you check the default python version after installing python33, you will see that the default version is still the same:
|
||||
|
||||
$ python --version
|
||||
|
||||
----------
|
||||
|
||||
Python 2.6.6
|
||||
|
||||
If you want to try an installed SCL package, you need to explicitly enable it "on a per-command basis" using scl:
|
||||
|
||||
$ scl enable <scl-package-name> <command>
|
||||
|
||||
For example, to enable python33 package for python command:
|
||||
|
||||
$ scl enable python33 'python --version'
|
||||
|
||||
----------
|
||||
|
||||
Python 3.3.2
|
||||
|
||||
If you want to run multiple commands while enabling python33 package, you can actually create an SCL-enabled bash session as follows.
|
||||
|
||||
$ scl enable python33 bash
|
||||
|
||||
Within this bash session, the default python will be switched to 3.3 until you type exit and kill the session.
|
||||
|
||||
|
||||
|
||||
In short, the SCL is somewhat similar to the virtualenv of Python, but is more general in that you can enable/disable SCL sessions for a far greater number of applications than just Python.
|
||||
|
||||
For more detailed instructions on the SCL, refer to the official [quick start guide][2].
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://xmodulo.com/enable-software-collections-centos.html
|
||||
|
||||
作者：[Dan Nanni][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://xmodulo.com/author/nanni
|
||||
[1]:https://www.softwarecollections.org/
|
||||
[2]:https://www.softwarecollections.org/docs/
|
||||
631
sources/tech/20151220 GCC-Inline-Assembly-HOWTO.md
Normal file
631
sources/tech/20151220 GCC-Inline-Assembly-HOWTO.md
Normal file
@ -0,0 +1,631 @@
|
||||
translate by zky001
|
||||
* * *
|
||||
|
||||
# GCC-Inline-Assembly-HOWTO
|
||||
v0.1, 01 March 2003.
|
||||
* * *
|
||||
|
||||
_This HOWTO explains the use and usage of the inline assembly feature provided by GCC. There are only two prerequisites for reading this article, and that’s obviously a basic knowledge of x86 assembly language and C._
|
||||
|
||||
* * *
|
||||
|
||||
## 1. Introduction.
|
||||
|
||||
## 1.1 Copyright and License.
|
||||
|
||||
Copyright (C)2003 Sandeep S.
|
||||
|
||||
This document is free; you can redistribute and/or modify this under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
|
||||
|
||||
This document is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
|
||||
|
||||
## 1.2 Feedback and Corrections.
|
||||
|
||||
Kindly forward feedback and criticism to [Sandeep.S](mailto:busybox@sancharnet.in). I will be indebted to anybody who points out errors and inaccuracies in this document; I shall rectify them as soon as I am informed.
|
||||
|
||||
## 1.3 Acknowledgments.
|
||||
|
||||
I express my sincere appreciation to GNU people for providing such a great feature. Thanks to Mr.Pramode C E for all the helps he did. Thanks to friends at the Govt Engineering College, Trichur for their moral-support and cooperation, especially to Nisha Kurur and Sakeeb S. Thanks to my dear teachers at Govt Engineering College, Trichur for their cooperation.
|
||||
|
||||
Additionally, thanks to Phillip, Brennan Underwood and colin@nyx.net; Many things here are shamelessly stolen from their works.
|
||||
|
||||
* * *
|
||||
|
||||
## 2. Overview of the whole thing.
|
||||
|
||||
We are here to learn about GCC inline assembly. What this inline stands for?
|
||||
|
||||
We can instruct the compiler to insert the code of a function into the code of its callers, to the point where actually the call is to be made. Such functions are inline functions. Sounds similar to a Macro? Indeed there are similarities.
|
||||
|
||||
What is the benefit of inline functions?
|
||||
|
||||
This method of inlining reduces the function-call overhead. And if any of the actual argument values are constant, their known values may permit simplifications at compile time so that not all of the inline function’s code needs to be included. The effect on code size is less predictable, it depends on the particular case. To declare an inline function, we’ve to use the keyword `inline` in its declaration.
|
||||
|
||||
Now we are in a position to guess what is inline assembly. Its just some assembly routines written as inline functions. They are handy, speedy and very much useful in system programming. Our main focus is to study the basic format and usage of (GCC) inline assembly functions. To declare inline assembly functions, we use the keyword `asm`.
|
||||
|
||||
Inline assembly is important primarily because of its ability to operate and make its output visible on C variables. Because of this capability, "asm" works as an interface between the assembly instructions and the "C" program that contains it.
|
||||
|
||||
* * *
|
||||
|
||||
## 3. GCC Assembler Syntax.
|
||||
|
||||
GCC, the GNU C Compiler for Linux, uses **AT&T**/**UNIX** assembly syntax. Here we’ll be using AT&T syntax for assembly coding. Don’t worry if you are not familiar with AT&T syntax, I will teach you. This is quite different from Intel syntax. I shall give the major differences.
|
||||
|
||||
1. Source-Destination Ordering.
|
||||
|
||||
The direction of the operands in AT&T syntax is opposite to that of Intel. In Intel syntax the first operand is the destination, and the second operand is the source whereas in AT&T syntax the first operand is the source and the second operand is the destination. ie,
|
||||
|
||||
"Op-code dst src" in Intel syntax changes to
|
||||
|
||||
"Op-code src dst" in AT&T syntax.
|
||||
|
||||
2. Register Naming.
|
||||
|
||||
Register names are prefixed by % ie, if eax is to be used, write %eax.
|
||||
|
||||
3. Immediate Operand.
|
||||
|
||||
AT&T immediate operands are preceded by ’$’. For static "C" variables also prefix a ’$’. In Intel syntax, for hexadecimal constants an ’h’ is suffixed, instead of that, here we prefix ’0x’ to the constant. So, for hexadecimals, we first see a ’$’, then ’0x’ and finally the constants.
|
||||
|
||||
4. Operand Size.
|
||||
|
||||
In AT&T syntax the size of memory operands is determined from the last character of the op-code name. Op-code suffixes of ’b’, ’w’, and ’l’ specify byte(8-bit), word(16-bit), and long(32-bit) memory references. Intel syntax accomplishes this by prefixing memory operands (not the op-codes) with ’byte ptr’, ’word ptr’, and ’dword ptr’.
|
||||
|
||||
Thus, Intel "mov al, byte ptr foo" is "movb foo, %al" in AT&T syntax.
|
||||
|
||||
5. Memory Operands.
|
||||
|
||||
In Intel syntax the base register is enclosed in ’[’ and ’]’ where as in AT&T they change to ’(’ and ’)’. Additionally, in Intel syntax an indirect memory reference is like
|
||||
|
||||
section:[base + index*scale + disp], which changes to
|
||||
|
||||
section:disp(base, index, scale) in AT&T.
|
||||
|
||||
One point to bear in mind is that, when a constant is used for disp/scale, ’$’ shouldn’t be prefixed.
|
||||
|
||||
Now we saw some of the major differences between Intel syntax and AT&T syntax. I’ve wrote only a few of them. For a complete information, refer to GNU Assembler documentations. Now we’ll look at some examples for better understanding.
|
||||
|
||||
> `
|
||||
>
|
||||
> <pre>+------------------------------+------------------------------------+
|
||||
> | Intel Code | AT&T Code |
|
||||
> +------------------------------+------------------------------------+
|
||||
> | mov eax,1 | movl $1,%eax |
|
||||
> | mov ebx,0ffh | movl $0xff,%ebx |
|
||||
> | int 80h | int $0x80 |
|
||||
> | mov ebx, eax | movl %eax, %ebx |
|
||||
> | mov eax,[ecx] | movl (%ecx),%eax |
|
||||
> | mov eax,[ebx+3] | movl 3(%ebx),%eax |
|
||||
> | mov eax,[ebx+20h] | movl 0x20(%ebx),%eax |
|
||||
> | add eax,[ebx+ecx*2h] | addl (%ebx,%ecx,0x2),%eax |
|
||||
> | lea eax,[ebx+ecx] | leal (%ebx,%ecx),%eax |
|
||||
> | sub eax,[ebx+ecx*4h-20h] | subl -0x20(%ebx,%ecx,0x4),%eax |
|
||||
> +------------------------------+------------------------------------+
|
||||
> </pre>
|
||||
>
|
||||
> `
|
||||
|
||||
* * *
|
||||
|
||||
## 4. Basic Inline.
|
||||
|
||||
The format of basic inline assembly is very much straight forward. Its basic form is
|
||||
|
||||
`asm("assembly code");`
|
||||
|
||||
Example.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre>asm("movl %ecx %eax"); /* moves the contents of ecx to eax */
|
||||
> __asm__("movb %bh (%eax)"); /*moves the byte from bh to the memory pointed by eax */
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
You might have noticed that here I’ve used `asm` and `__asm__`. Both are valid. We can use `__asm__` if the keyword `asm` conflicts with something in our program. If we have more than one instructions, we write one per line in double quotes, and also suffix a ’\n’ and ’\t’ to the instruction. This is because gcc sends each instruction as a string to **as**(GAS) and by using the newline/tab we send correctly formatted lines to the assembler.
|
||||
|
||||
Example.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre> __asm__ ("movl %eax, %ebx\n\t"
|
||||
> "movl $56, %esi\n\t"
|
||||
> "movl %ecx, $label(%edx,%ebx,$4)\n\t"
|
||||
> "movb %ah, (%ebx)");
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
If in our code we touch (ie, change the contents) some registers and return from asm without fixing those changes, something bad is going to happen. This is because GCC have no idea about the changes in the register contents and this leads us to trouble, especially when compiler makes some optimizations. It will suppose that some register contains the value of some variable that we might have changed without informing GCC, and it continues like nothing happened. What we can do is either use those instructions having no side effects or fix things when we quit or wait for something to crash. This is where we want some extended functionality. Extended asm provides us with that functionality.
|
||||
|
||||
* * *
|
||||
|
||||
## 5. Extended Asm.
|
||||
|
||||
In basic inline assembly, we had only instructions. In extended assembly, we can also specify the operands. It allows us to specify the input registers, output registers and a list of clobbered registers. It is not mandatory to specify the registers to use, we can leave that head ache to GCC and that probably fit into GCC’s optimization scheme better. Anyway the basic format is:
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre> asm ( assembler template
|
||||
> : output operands /* optional */
|
||||
> : input operands /* optional */
|
||||
> : list of clobbered registers /* optional */
|
||||
> );
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
The assembler template consists of assembly instructions. Each operand is described by an operand-constraint string followed by the C expression in parentheses. A colon separates the assembler template from the first output operand and another separates the last output operand from the first input, if any. Commas separate the operands within each group. The total number of operands is limited to ten or to the maximum number of operands in any instruction pattern in the machine description, whichever is greater.
|
||||
|
||||
If there are no output operands but there are input operands, you must place two consecutive colons surrounding the place where the output operands would go.
|
||||
|
||||
Example:
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre> asm ("cld\n\t"
|
||||
> "rep\n\t"
|
||||
> "stosl"
|
||||
> : /* no output registers */
|
||||
> : "c" (count), "a" (fill_value), "D" (dest)
|
||||
> : "%ecx", "%edi"
|
||||
> );
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
Now, what does this code do? The above inline fills the `fill_value` `count` times to the location pointed to by the register `edi`. It also says to gcc that, the contents of registers `eax` and `edi` are no longer valid. Let us see one more example to make things more clearer.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre>
|
||||
> int a=10, b;
|
||||
> asm ("movl %1, %%eax;
|
||||
> movl %%eax, %0;"
|
||||
> :"=r"(b) /* output */
|
||||
> :"r"(a) /* input */
|
||||
> :"%eax" /* clobbered register */
|
||||
> );
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
Here what we did is we made the value of ’b’ equal to that of ’a’ using assembly instructions. Some points of interest are:
|
||||
|
||||
* "b" is the output operand, referred to by %0 and "a" is the input operand, referred to by %1.
|
||||
* "r" is a constraint on the operands. We’ll see constraints in detail later. For the time being, "r" says to GCC to use any register for storing the operands. output operand constraint should have a constraint modifier "=". And this modifier says that it is the output operand and is write-only.
|
||||
* There are two %’s prefixed to the register name. This helps GCC to distinguish between the operands and registers. operands have a single % as prefix.
|
||||
* The clobbered register %eax after the third colon tells GCC that the value of %eax is to be modified inside "asm", so GCC won’t use this register to store any other value.
|
||||
|
||||
When the execution of "asm" is complete, "b" will reflect the updated value, as it is specified as an output operand. In other words, the change made to "b" inside "asm" is supposed to be reflected outside the "asm".
|
||||
|
||||
Now we may look each field in detail.
|
||||
|
||||
## 5.1 Assembler Template.
|
||||
|
||||
The assembler template contains the set of assembly instructions that gets inserted inside the C program. The format is like: either each instruction should be enclosed within double quotes, or the entire group of instructions should be within double quotes. Each instruction should also end with a delimiter. The valid delimiters are newline(\n) and semicolon(;). ’\n’ may be followed by a tab(\t). We know the reason of newline/tab, right?. Operands corresponding to the C expressions are represented by %0, %1 ... etc.
|
||||
|
||||
## 5.2 Operands.
|
||||
|
||||
C expressions serve as operands for the assembly instructions inside "asm". Each operand is written as first an operand constraint in double quotes. For output operands, there’ll be a constraint modifier also within the quotes and then follows the C expression which stands for the operand. ie,
|
||||
|
||||
"constraint" (C expression) is the general form. For output operands an additional modifier will be there. Constraints are primarily used to decide the addressing modes for operands. They are also used in specifying the registers to be used.
|
||||
|
||||
If we use more than one operand, they are separated by comma.
|
||||
|
||||
In the assembler template, each operand is referenced by numbers. Numbering is done as follows. If there are a total of n operands (both input and output inclusive), then the first output operand is numbered 0, continuing in increasing order, and the last input operand is numbered n-1\. The maximum number of operands is as we saw in the previous section.
|
||||
|
||||
Output operand expressions must be lvalues. The input operands are not restricted like this. They may be expressions. The extended asm feature is most often used for machine instructions the compiler itself does not know as existing ;-). If the output expression cannot be directly addressed (for example, it is a bit-field), our constraint must allow a register. In that case, GCC will use the register as the output of the asm, and then store that register contents into the output.
|
||||
|
||||
As stated above, ordinary output operands must be write-only; GCC will assume that the values in these operands before the instruction are dead and need not be generated. Extended asm also supports input-output or read-write operands.
|
||||
|
||||
So now we concentrate on some examples. We want to multiply a number by 5\. For that we use the instruction `lea`.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre> asm ("leal (%1,%1,4), %0"
|
||||
> : "=r" (five_times_x)
|
||||
> : "r" (x)
|
||||
> );
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
Here our input is in ’x’. We didn’t specify the register to be used. GCC will choose some register for input, one for output and does what we desired. If we want the input and output to reside in the same register, we can instruct GCC to do so. Here we use those types of read-write operands. By specifying proper constraints, here we do it.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre> asm ("leal (%0,%0,4), %0"
|
||||
> : "=r" (five_times_x)
|
||||
> : "0" (x)
|
||||
> );
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
Now the input and output operands are in the same register. But we don’t know which register. Now if we want to specify that also, there is a way.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre> asm ("leal (%%ecx,%%ecx,4), %%ecx"
|
||||
> : "=c" (x)
|
||||
> : "c" (x)
|
||||
> );
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
In all the three examples above, we didn’t put any register to the clobber list. why? In the first two examples, GCC decides the registers and it knows what changes happen. In the last one, we don’t have to put `ecx` on the c lobberlist, gcc knows it goes into x. Therefore, since it can know the value of `ecx`, it isn’t considered clobbered.
|
||||
|
||||
## 5.3 Clobber List.
|
||||
|
||||
Some instructions clobber some hardware registers. We have to list those registers in the clobber-list, ie the field after the third ’**:**’ in the asm function. This is to inform gcc that we will use and modify them ourselves. So gcc will not assume that the values it loads into these registers will be valid. We shoudn’t list the input and output registers in this list. Because, gcc knows that "asm" uses them (because they are specified explicitly as constraints). If the instructions use any other registers, implicitly or explicitly (and the registers are not present either in input or in the output constraint list), then those registers have to be specified in the clobbered list.
|
||||
|
||||
If our instruction can alter the condition code register, we have to add "cc" to the list of clobbered registers.
|
||||
|
||||
If our instruction modifies memory in an unpredictable fashion, add "memory" to the list of clobbered registers. This will cause GCC to not keep memory values cached in registers across the assembler instruction. We also have to add the **volatile** keyword if the memory affected is not listed in the inputs or outputs of the asm.
|
||||
|
||||
We can read and write the clobbered registers as many times as we like. Consider the example of multiple instructions in a template; it assumes the subroutine _foo accepts arguments in registers `eax` and `ecx`.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre> asm ("movl %0,%%eax;
|
||||
> movl %1,%%ecx;
|
||||
> call _foo"
|
||||
> : /* no outputs */
|
||||
> : "g" (from), "g" (to)
|
||||
> : "eax", "ecx"
|
||||
> );
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
## 5.4 Volatile ...?
|
||||
|
||||
If you are familiar with kernel sources or some beautiful code like that, you must have seen many functions declared as `volatile` or `__volatile__` which follows an `asm` or `__asm__`. I mentioned earlier about the keywords `asm` and `__asm__`. So what is this `volatile`?
|
||||
|
||||
If our assembly statement must execute where we put it, (i.e. must not be moved out of a loop as an optimization), put the keyword `volatile` after asm and before the ()’s. So to keep it from moving, deleting and all, we declare it as
|
||||
|
||||
`asm volatile ( ... : ... : ... : ...);`
|
||||
|
||||
Use `__volatile__` when we have to be verymuch careful.
|
||||
|
||||
If our assembly is just for doing some calculations and doesn’t have any side effects, it’s better not to use the keyword `volatile`. Avoiding it helps gcc in optimizing the code and making it more beautiful.
|
||||
|
||||
In the section `Some Useful Recipes`, I have provided many examples for inline asm functions. There we can see the clobber-list in detail.
|
||||
|
||||
* * *
|
||||
|
||||
## 6. More about constraints.
|
||||
|
||||
By this time, you might have understood that constraints have got a lot to do with inline assembly. But we’ve said little about constraints. Constraints can say whether an operand may be in a register, and which kinds of register; whether the operand can be a memory reference, and which kinds of address; whether the operand may be an immediate constant, and which possible values (ie range of values) it may have.... etc.
|
||||
|
||||
## 6.1 Commonly used constraints.
|
||||
|
||||
There are a number of constraints of which only a few are used frequently. We’ll have a look at those constraints.
|
||||
|
||||
1. **Register operand constraint(r)**
|
||||
|
||||
When operands are specified using this constraint, they get stored in General Purpose Registers(GPR). Take the following example:
|
||||
|
||||
`asm ("movl %%eax, %0\n" :"=r"(myval));`
|
||||
|
||||
Here the variable myval is kept in a register, the value in register `eax` is copied onto that register, and the value of `myval` is updated into the memory from this register. When the "r" constraint is specified, gcc may keep the variable in any of the available GPRs. To specify the register, you must directly specify the register names by using specific register constraints. They are:
|
||||
|
||||
> `
|
||||
>
|
||||
> <pre>+---+--------------------+
|
||||
> | r | Register(s) |
|
||||
> +---+--------------------+
|
||||
> | a | %eax, %ax, %al |
|
||||
> | b | %ebx, %bx, %bl |
|
||||
> | c | %ecx, %cx, %cl |
|
||||
> | d | %edx, %dx, %dl |
|
||||
> | S | %esi, %si |
|
||||
> | D | %edi, %di |
|
||||
> +---+--------------------+
|
||||
> </pre>
|
||||
>
|
||||
> `
|
||||
|
||||
2. **Memory operand constraint(m)**
|
||||
|
||||
When the operands are in the memory, any operations performed on them will occur directly in the memory location, as opposed to register constraints, which first store the value in a register to be modified and then write it back to the memory location. But register constraints are usually used only when they are absolutely necessary for an instruction or they significantly speed up the process. Memory constraints can be used most efficiently in cases where a C variable needs to be updated inside "asm" and you really don’t want to use a register to hold its value. For example, the value of idtr is stored in the memory location loc:
|
||||
|
||||
`asm("sidt %0\n" : :"m"(loc));`
|
||||
|
||||
3. **Matching(Digit) constraints**
|
||||
|
||||
In some cases, a single variable may serve as both the input and the output operand. Such cases may be specified in "asm" by using matching constraints.
|
||||
|
||||
`asm ("incl %0" :"=a"(var):"0"(var));`
|
||||
|
||||
We saw similar examples in operands subsection also. In this example for matching constraints, the register %eax is used as both the input and the output variable. var input is read to %eax and updated %eax is stored in var again after increment. "0" here specifies the same constraint as the 0th output variable. That is, it specifies that the output instance of var should be stored in %eax only. This constraint can be used:
|
||||
|
||||
* In cases where input is read from a variable or the variable is modified and modification is written back to the same variable.
|
||||
* In cases where separate instances of input and output operands are not necessary.
|
||||
|
||||
The most important effect of using matching restraints is that they lead to the efficient use of available registers.
|
||||
|
||||
Some other constraints used are:
|
||||
|
||||
1. "m" : A memory operand is allowed, with any kind of address that the machine supports in general.
|
||||
2. "o" : A memory operand is allowed, but only if the address is offsettable. ie, adding a small offset to the address gives a valid address.
|
||||
3. "V" : A memory operand that is not offsettable. In other words, anything that would fit the `m’ constraint but not the `o’constraint.
|
||||
4. "i" : An immediate integer operand (one with constant value) is allowed. This includes symbolic constants whose values will be known only at assembly time.
|
||||
5. "n" : An immediate integer operand with a known numeric value is allowed. Many systems cannot support assembly-time constants for operands less than a word wide. Constraints for these operands should use ’n’ rather than ’i’.
|
||||
6. "g" : Any register, memory or immediate integer operand is allowed, except for registers that are not general registers.
|
||||
|
||||
Following constraints are x86 specific.
|
||||
|
||||
1. "r" : Register operand constraint, look table given above.
|
||||
2. "q" : Registers a, b, c or d.
|
||||
3. "I" : Constant in range 0 to 31 (for 32-bit shifts).
|
||||
4. "J" : Constant in range 0 to 63 (for 64-bit shifts).
|
||||
5. "K" : 0xff.
|
||||
6. "L" : 0xffff.
|
||||
7. "M" : 0, 1, 2, or 3 (shifts for lea instruction).
|
||||
8. "N" : Constant in range 0 to 255 (for out instruction).
|
||||
9. "f" : Floating point register
|
||||
10. "t" : First (top of stack) floating point register
|
||||
11. "u" : Second floating point register
|
||||
12. "A" : Specifies the `a’ or `d’ registers. This is primarily useful for 64-bit integer values intended to be returned with the `d’ register holding the most significant bits and the `a’ register holding the least significant bits.
|
||||
|
||||
## 6.2 Constraint Modifiers.
|
||||
|
||||
While using constraints, for more precise control over the effects of constraints, GCC provides us with constraint modifiers. Mostly used constraint modifiers are
|
||||
|
||||
1. "=" : Means that this operand is write-only for this instruction; the previous value is discarded and replaced by output data.
|
||||
2. "&" : Means that this operand is an earlyclobber operand, which is modified before the instruction is finished using the input operands. Therefore, this operand may not lie in a register that is used as an input operand or as part of any memory address. An input operand can be tied to an earlyclobber operand if its only use as an input occurs before the early result is written.
|
||||
|
||||
The list and explanation of constraints is by no means complete. Examples can give a better understanding of the use and usage of inline asm. In the next section we’ll see some examples, there we’ll find more about clobber-lists and constraints.
|
||||
|
||||
* * *
|
||||
|
||||
## 7. Some Useful Recipes.
|
||||
|
||||
Now we have covered the basic theory about GCC inline assembly, now we shall concentrate on some simple examples. It is always handy to write inline asm functions as MACRO’s. We can see many asm functions in the kernel code. (/usr/src/linux/include/asm/*.h).
|
||||
|
||||
1. First we start with a simple example. We’ll write a program to add two numbers.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre>int main(void)
|
||||
> {
|
||||
> int foo = 10, bar = 15;
|
||||
> __asm__ __volatile__("addl %%ebx,%%eax"
|
||||
> :"=a"(foo)
|
||||
> :"a"(foo), "b"(bar)
|
||||
> );
|
||||
> printf("foo+bar=%d\n", foo);
|
||||
> return 0;
|
||||
> }
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
Here we insist GCC to store foo in %eax, bar in %ebx and we also want the result in %eax. The ’=’ sign shows that it is an output register. Now we can add an integer to a variable in some other way.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre> __asm__ __volatile__(
|
||||
> " lock ;\n"
|
||||
> " addl %1,%0 ;\n"
|
||||
> : "=m" (my_var)
|
||||
> : "ir" (my_int), "m" (my_var)
|
||||
> : /* no clobber-list */
|
||||
> );
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
This is an atomic addition. We can remove the instruction ’lock’ to remove the atomicity. In the output field, "=m" says that my_var is an output and it is in memory. Similarly, "ir" says that, my_int is an integer and should reside in some register (recall the table we saw above). No registers are in the clobber list.
|
||||
|
||||
2. Now we’ll perform some action on some registers/variables and compare the value.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre> __asm__ __volatile__( "decl %0; sete %1"
|
||||
> : "=m" (my_var), "=q" (cond)
|
||||
> : "m" (my_var)
|
||||
> : "memory"
|
||||
> );
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
Here, the value of my_var is decremented by one and if the resulting value is `0` then, the variable cond is set. We can add atomicity by adding an instruction "lock;\n\t" as the first instruction in assembler template.
|
||||
|
||||
In a similar way we can use "incl %0" instead of "decl %0", so as to increment my_var.
|
||||
|
||||
Points to note here are that (i) my_var is a variable residing in memory. (ii) cond is in any of the registers eax, ebx, ecx and edx. The constraint "=q" guarantees it. (iii) And we can see that memory is there in the clobber list. ie, the code is changing the contents of memory.
|
||||
|
||||
3. How to set/clear a bit in a register? As next recipe, we are going to see it.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre>__asm__ __volatile__( "btsl %1,%0"
|
||||
> : "=m" (ADDR)
|
||||
> : "Ir" (pos)
|
||||
> : "cc"
|
||||
> );
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
Here, the bit at the position ’pos’ of variable at ADDR ( a memory variable ) is set to `1` We can use ’btrl’ for ’btsl’ to clear the bit. The constraint "Ir" of pos says that, pos is in a register, and it’s value ranges from 0-31 (x86 dependant constraint). ie, we can set/clear any bit from 0th to 31st of the variable at ADDR. As the condition codes will be changed, we are adding "cc" to clobberlist.
|
||||
|
||||
4. Now we look at some more complicated but useful function. String copy.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre>static inline char * strcpy(char * dest,const char *src)
|
||||
> {
|
||||
> int d0, d1, d2;
|
||||
> __asm__ __volatile__( "1:\tlodsb\n\t"
|
||||
> "stosb\n\t"
|
||||
> "testb %%al,%%al\n\t"
|
||||
> "jne 1b"
|
||||
> : "=&S" (d0), "=&D" (d1), "=&a" (d2)
|
||||
> : "0" (src),"1" (dest)
|
||||
> : "memory");
|
||||
> return dest;
|
||||
> }
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
The source address is stored in esi, destination in edi, and then starts the copy, when we reach at **0**, copying is complete. Constraints "&S", "&D", "&a" say that the registers esi, edi and eax are early clobber registers, ie, their contents will change before the completion of the function. Here also it’s clear that why memory is in clobberlist.
|
||||
|
||||
We can see a similar function which moves a block of double words. Notice that the function is declared as a macro.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre>#define mov_blk(src, dest, numwords) \
|
||||
> __asm__ __volatile__ ( \
|
||||
> "cld\n\t" \
|
||||
> "rep\n\t" \
|
||||
> "movsl" \
|
||||
> : \
|
||||
> : "S" (src), "D" (dest), "c" (numwords) \
|
||||
> : "%ecx", "%esi", "%edi" \
|
||||
> )
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
Here we have no outputs, so the changes that happen to the contents of the registers ecx, esi and edi are side effects of the block movement. So we have to add them to the clobber list.
|
||||
|
||||
5. In Linux, system calls are implemented using GCC inline assembly. Let us look how a system call is implemented. All the system calls are written as macros (linux/unistd.h). For example, a system call with three arguments is defined as a macro as shown below.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre>#define _syscall3(type,name,type1,arg1,type2,arg2,type3,arg3) \
|
||||
> type name(type1 arg1,type2 arg2,type3 arg3) \
|
||||
> { \
|
||||
> long __res; \
|
||||
> __asm__ volatile ( "int $0x80" \
|
||||
> : "=a" (__res) \
|
||||
> : "0" (__NR_##name),"b" ((long)(arg1)),"c" ((long)(arg2)), \
|
||||
> "d" ((long)(arg3))); \
|
||||
> __syscall_return(type,__res); \
|
||||
> }
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
Whenever a system call with three arguments is made, the macro shown above is used to make the call. The syscall number is placed in eax, then each parameters in ebx, ecx, edx. And finally "int 0x80" is the instruction which makes the system call work. The return value can be collected from eax.
|
||||
|
||||
Every system calls are implemented in a similar way. Exit is a single parameter syscall and let’s see how it’s code will look like. It is as shown below.
|
||||
|
||||
> `
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> <pre>{
|
||||
> asm("movl $1,%%eax; /* SYS_exit is 1 */
|
||||
> xorl %%ebx,%%ebx; /* Argument is in ebx, it is 0 */
|
||||
> int $0x80" /* Enter kernel mode */
|
||||
> );
|
||||
> }
|
||||
> </pre>
|
||||
>
|
||||
> * * *
|
||||
>
|
||||
> `
|
||||
|
||||
The number of exit is "1" and here, it’s parameter is 0\. So we arrange eax to contain 1 and ebx to contain 0 and by `int $0x80`, the `exit(0)` is executed. This is how exit works.
|
||||
|
||||
* * *
|
||||
|
||||
## 8. Concluding Remarks.
|
||||
|
||||
This document has gone through the basics of GCC Inline Assembly. Once you have understood the basic concept it is not difficult to take steps by your own. We saw some examples which are helpful in understanding the frequently used features of GCC Inline Assembly.
|
||||
|
||||
GCC Inlining is a vast subject and this article is by no means complete. More details about the syntax’s we discussed about is available in the official documentation for GNU Assembler. Similarly, for a complete list of the constraints refer to the official documentation of GCC.
|
||||
|
||||
And of-course, the Linux kernel use GCC Inline in a large scale. So we can find many examples of various kinds in the kernel sources. They can help us a lot.
|
||||
|
||||
If you have found any glaring typos, or outdated info in this document, please let us know.
|
||||
|
||||
* * *
|
||||
|
||||
## 9. References.
|
||||
|
||||
1. [Brennan’s Guide to Inline Assembly](http://www.delorie.com/djgpp/doc/brennan/brennan_att_inline_djgpp.html)
|
||||
2. [Using Assembly Language in Linux](http://linuxassembly.org/articles/linasm.html)
|
||||
3. [Using as, The GNU Assembler](http://www.gnu.org/manual/gas-2.9.1/html_mono/as.html)
|
||||
4. [Using and Porting the GNU Compiler Collection (GCC)](http://gcc.gnu.org/onlinedocs/gcc_toc.html)
|
||||
5. [Linux Kernel Source](http://ftp.kernel.org/)
|
||||
|
||||
* * *
|
||||
via: http://www.ibiblio.org/gferg/ldp/GCC-Inline-Assembly-HOWTO.html
|
||||
|
||||
作者：[Sandeep.S](mailto:busybox@sancharnet.in) 译者：[zky001](https://github.com/zky001) 校对：[]()
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创翻译，[Linux中国](http://linux.cn/) 荣誉推出
|
||||
86
sources/tech/20151222 Turn Tor socks to http.md
Normal file
86
sources/tech/20151222 Turn Tor socks to http.md
Normal file
@ -0,0 +1,86 @@
|
||||
Turn Tor socks to http
|
||||
================================================================================
|
||||
|
||||
|
||||
For using Tor service you can use diffrent tools like Tor browser, Foxyproxy and other things, some download managers such as Wget or Aria2 can’t get Tor socks directly and start downloading anonymously with that so we need some tools to change Tor socks to http and then download with that.
|
||||
|
||||
**Note** : This tutorial is under Debian distrobutions and in other distrobutions may be diffrent so if your distro is Debian base and you have configured Tor correctly go a head !
|
||||
|
||||
**Polipo** : This service uses 8123 Port and 127.0.0.1 IP, use following command to install Polipo on your computer :
|
||||
|
||||
sudo apt install polipo
|
||||
|
||||
Now use this command to go in Polipo config file:
|
||||
|
||||
sudo nano /etc/polipo/config
|
||||
|
||||
Add the following lines to the end of the file :
|
||||
|
||||
proxyAddress = "::0"
|
||||
allowedClients = 192.168.1.0/24
|
||||
socksParentProxy = "localhost:9050"
|
||||
socksProxyType = socks5
|
||||
|
||||
Restart the Polipo service with this command :
|
||||
|
||||
sudo service polipo restart
|
||||
|
||||
Now Polipo is ready ! do what ever you like in anonymous world ! as example of how using it :
|
||||
|
||||
pdmt -l "link" -i 127.0.01 -p 8123
|
||||
|
||||
With command above, PDMT ( Persian Download Manager Terminal ) will download your file anonymously.
|
||||
|
||||
**Proxychains** : In this service you can set Tor or Lantern proxy to turn socks too but in usage it’s a little diffrent with Polipo and Privoxy because you don’t need to use any port ! for installing that use following command :
|
||||
|
||||
sudo apt install proxychains
|
||||
|
||||
Open config file with this command :
|
||||
|
||||
sudo nano /etc/proxychains.conf
|
||||
|
||||
Now add the following code to the end of text, this code is Tor port and Ip :
|
||||
|
||||
socks5 127.0.0.1 9050
|
||||
|
||||
If you put “proxychains” word before a command in terminal and run it, it would run by Tor proxy :
|
||||
|
||||
proxychains firefoxt
|
||||
proxychains aria2c
|
||||
proxychains wget
|
||||
|
||||
**Privoxy** : Privoxy uses 8118 port and it’s easy to run first install privoxy package :
|
||||
|
||||
sudo apt install privoxy
|
||||
|
||||
We should change the config file now :
|
||||
|
||||
sudo nano /etc/pivoxy/config
|
||||
|
||||
Add the following lines to end of the file :
|
||||
|
||||
forward-socks5 / 127.0.0.1:9050 .
|
||||
forward-socks4a / 127.0.0.1:9050 .
|
||||
forward-socks5t / 127.0.0.1:9050 .
|
||||
forward 192.168.*.*/ .
|
||||
forward 10.*.*.*/ .
|
||||
forward 127.*.*.*/ .
|
||||
forward localhost/ .
|
||||
|
||||
Restart the service :
|
||||
|
||||
sudo service privoxy restart
|
||||
|
||||
Service is ready ! port is 8118 and Ip is 127.0.0.1 use it and enjoy from it !
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.unixmen.com/turn-tor-socks-http/
|
||||
|
||||
作者：[Hossein heydari][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://www.unixmen.com/author/hossein/
|
||||
@ -1,121 +0,0 @@
|
||||
Learn with Linux: Learning to Type
|
||||
================================================================================
|
||||
|
||||
|
||||
This article is part of the [Learn with Linux][1] series:
|
||||
|
||||
- [Learn with Linux: Learning to Type][2]
|
||||
- [Learn with Linux: Physics Simulation][3]
|
||||
- [Learn with Linux: Learning Music][4]
|
||||
- [Learn with Linux: Two Geography Apps][5]
|
||||
- [Learn with Linux: Master Your Math with These Linux Apps][6]
|
||||
|
||||
Linux offers great educational software and many excellent tools to aid students of all grades and ages in learning and practicing a variety of topics, often interactively. The “Learn with Linux” series of articles offers an introduction to a variety of educational apps and software.
|
||||
|
||||
Typing is taken for granted by many people; today being keyboard savvy often comes as second nature. Yet how many of us still type with two fingers, even if ever so fast? Once typing was taught in schools, but slowly the art of ten-finger typing is giving way to two thumbs.
|
||||
|
||||
The following two applications can help you master the keyboard so that your next thought does not get lost while your fingers catch up. They were chosen for their simplicity and ease of use. While there are some more flashy or better looking typing apps out there, the following two will get the basics covered and offer the easiest way to start out.
|
||||
|
||||
### TuxType (or TuxTyping) ###
|
||||
|
||||
TuxType is for children. Young students can learn how to type with ten fingers with simple lessons and practice their newly-acquired skills in fun games.
|
||||
|
||||
Debian and derivatives (therefore all Ubuntu derivatives) should have TuxType in their standard repositories. To install simply type
|
||||
|
||||
sudo apt-get install tuxtype
|
||||
|
||||
The application starts with a simple menu screen featuring Tux and some really bad midi music (Fortunately the sound can be turned off easily with the icon in the lower left corner.).
|
||||
|
||||
|
||||
|
||||
The top two choices, “Fish Cascade” and “Comet Zap,” represent typing games, but to start learning you need to head over to the lessons.
|
||||
|
||||
There are forty simple built-in lessons to choose from. Each one of these will take a letter from the keyboard and make the student practice while giving visual hints, such as which finger to use.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
For more advanced practice, phrase typing is also available, although for some reason this is hidden under the options menu.
|
||||
|
||||
|
||||
|
||||
The games are good for speed and accuracy as the player helps Tux catch falling fish
|
||||
|
||||
|
||||
|
||||
or zap incoming asteroids by typing the words written over them.
|
||||
|
||||
|
||||
|
||||
Besides being a fun way to practice, these games teach spelling, speed, and eye-to-hand coordination, as you must type while also watching the screen, building a foundation for touch typing, if taken seriously.
|
||||
|
||||
### GNU typist (gtype) ###
|
||||
|
||||
For adults and more experienced typists, there is GNU Typist, a console-based application developed by the GNU project.
|
||||
|
||||
GNU Typist will also be carried by most Debian derivatives’ main repos. Installing it is as easy as typing
|
||||
|
||||
sudo apt-get install gtype
|
||||
|
||||
You will probably not find it in the Applications menu; insteaad you should start it from a terminal window.
|
||||
|
||||
gtype
|
||||
|
||||
The main menu is simple, no-nonsense and frill-free, yet it is evident how much the software has to offer. Typing lessons of all levels are immediately accessible.
|
||||
|
||||
|
||||
|
||||
The lessons are straightforward and detailed.
|
||||
|
||||
|
||||
|
||||
The interactive practice sessions offer little more than highlighting your mistakes. Instead of flashy visuals you have to chance to focus on practising. At the end of each lesson you get some simple statistics of how you’ve been doing. If you make too many mistakes, you cannot proceed until you can pass the level.
|
||||
|
||||
|
||||
|
||||
While the basic lessons only require you to repeat some characters, more advanced drills will have the practitioner type either whole sentences,
|
||||
|
||||
|
||||
|
||||
where of course the three percent error margin means you are allowed even fewer mistakes,
|
||||
|
||||
|
||||
|
||||
or some drills aiming to achieve certain goals, as in the “Balanced keyboard drill.”
|
||||
|
||||
|
||||
|
||||
Simple speed drills have you type quotes,
|
||||
|
||||
|
||||
|
||||
while more advanced ones will make you write longer texts taken from classics.
|
||||
|
||||
|
||||
|
||||
If you’d prefer a different language, more lessons can also be loaded as command line arguments.
|
||||
|
||||
|
||||
|
||||
### Conclusion ###
|
||||
|
||||
If you care to hone your typing skills, Linux has great software to offer. The two basic, yet feature-rich, applications discussed above will cater to most aspiring typists’ needs. If you use or know of another great typing application, please don’t hesitate to let us know below in the comments.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.maketecheasier.com/learn-to-type-in-linux/
|
||||
|
||||
作者：[Attila Orosz][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.maketecheasier.com/author/attilaorosz/
|
||||
[1]:https://www.maketecheasier.com/series/learn-with-linux/
|
||||
[2]:https://www.maketecheasier.com/learn-to-type-in-linux/
|
||||
[3]:https://www.maketecheasier.com/linux-physics-simulation/
|
||||
[4]:https://www.maketecheasier.com/linux-learning-music/
|
||||
[5]:https://www.maketecheasier.com/linux-geography-apps/
|
||||
[6]:https://www.maketecheasier.com/learn-linux-maths/
|
||||
@ -1,103 +0,0 @@
|
||||
Learn with Linux: Two Geography Apps
|
||||
================================================================================
|
||||
|
||||
|
||||
This article is part of the [Learn with Linux][1] series:
|
||||
|
||||
- [Learn with Linux: Learning to Type][2]
|
||||
- [Learn with Linux: Physics Simulation][3]
|
||||
- [Learn with Linux: Learning Music][4]
|
||||
- [Learn with Linux: Two Geography Apps][5]
|
||||
- [Learn with Linux: Master Your Math with These Linux Apps][6]
|
||||
|
||||
Linux offers great educational software and many excellent tools to aid students of all grades and ages in learning and practicing a variety of topics, often interactively. The “Learn with Linux” series of articles offers an introduction to a variety of educational apps and software.
|
||||
|
||||
Geography is an interesting subject, used by many of us day to day, often without realizing. But when you fire up GPS, SatNav, or just Google maps, you are using the geographical data provided by this software with the maps drawn by cartographists. When you hear about a certain country in the news or hear financial data being recited, these all fall under the umbrella of geography. And you have some great Linux software to study and practice these, whether it is for school or your own improvement.
|
||||
|
||||
### Kgeography ###
|
||||
|
||||
There are only two geography-related applications readily available in most Linux repositories, and both of these are KDE applications, in fact part of the KDE Educatonal project. Kgeography uses simple color-coded maps of any selected country.
|
||||
|
||||
To install kegeography just type
|
||||
|
||||
sudo apt-get install kgeography
|
||||
|
||||
into a terminal window of any Ubuntu-based distribution.
|
||||
|
||||
The interface is very basic. You are first presented with a picker menu that lets you choose an area map.
|
||||
|
||||
|
||||
|
||||
On the map you can display the name and capital of any given territory by clicking on it,
|
||||
|
||||
|
||||
|
||||
and test your knowledge in different quizzes.
|
||||
|
||||
|
||||
|
||||
It is an interactive way to test your basic geographical knowledge and could be an excellent tool to help you prepare for exams.
|
||||
|
||||
### Marble ###
|
||||
|
||||
Marble is a somewhat more advanced software, offering a global view of the world without the need of 3D acceleration.
|
||||
|
||||
|
||||
|
||||
To get Marble, type
|
||||
|
||||
sudo apt-get install marble
|
||||
|
||||
into a terminal window of any Ubuntu-based distribution.
|
||||
|
||||
Marble focuses on cartography, its main view being that of an atlas.
|
||||
|
||||
|
||||
|
||||
You can have different projections, like Globe or Mercator displayed as defaults, with flat and other exotic views available from a drop-down menu. The surfaces include the basic Atlas view, a full-fledged offline map powered by OpenStreetMap,
|
||||
|
||||
|
||||
|
||||
satellite view (by NASA),
|
||||
|
||||
|
||||
|
||||
and political and even historical maps of the world, among others.
|
||||
|
||||
|
||||
|
||||
Besides providing great offline maps with different skins and varying amount of data, Marble offers other types of information as well. You can switch on and off various offline info-boxes
|
||||
|
||||
|
||||
|
||||
and online services from the menu.
|
||||
|
||||
|
||||
|
||||
An interesting online service is Wikipedia integration. Clicking on the little Wiki logos will bring up a pop-up featuring detailed information about the selected places.
|
||||
|
||||
|
||||
|
||||
The software also includes options for location tracking, route planning, and searching for locations, among other great and useful features. If you enjoy cartography, Marble offers hours of fun exploring and learning.
|
||||
|
||||
### Conclusion ###
|
||||
|
||||
Linux offers many great educational applications, and the subject of geography is no exception. With the above two programs you can learn a lot about our globe and test your knowledge in a fun and interactive manner.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.maketecheasier.com/linux-geography-apps/
|
||||
|
||||
作者：[Attila Orosz][a]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.maketecheasier.com/author/attilaorosz/
|
||||
[1]:https://www.maketecheasier.com/series/learn-with-linux/
|
||||
[2]:https://www.maketecheasier.com/learn-to-type-in-linux/
|
||||
[3]:https://www.maketecheasier.com/linux-physics-simulation/
|
||||
[4]:https://www.maketecheasier.com/linux-learning-music/
|
||||
[5]:https://www.maketecheasier.com/linux-geography-apps/
|
||||
[6]:https://www.maketecheasier.com/learn-linux-maths/
|
||||
@ -1,3 +1,4 @@
|
||||
(translating by runningwater)
|
||||
Grep Count Lines If a String / Word Matches
|
||||
================================================================================
|
||||
How do I count lines if given word or string matches for each input file under Linux or UNIX operating systems?
|
||||
@ -27,7 +28,7 @@ Sample outputs:
|
||||
via: http://www.cyberciti.biz/faq/grep-count-lines-if-a-string-word-matches/
|
||||
|
||||
作者：Vivek Gite
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
译者：[runningwater](https://github.com/runningwater)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
@ -1,3 +1,4 @@
|
||||
(translating by runningwater)
|
||||
Grep From Files and Display the File Name
|
||||
================================================================================
|
||||
How do I grep from a number of files and display the file name only?
|
||||
@ -61,7 +62,7 @@ Sample outputs:
|
||||
via: http://www.cyberciti.biz/faq/grep-from-files-and-display-the-file-name/
|
||||
|
||||
作者：Vivek Gite
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
译者：[runningwater](https://github.com/runningwater)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
@ -0,0 +1,209 @@
|
||||
# 19年KDE进化历程
|
||||
注：youtube 视频
|
||||
<iframe width="660" height="371" src="https://www.youtube.com/embed/1UG4lQOMBC4?feature=oembed" frameborder="0" allowfullscreen></iframe>
|
||||
|
||||
## 概述
|
||||
KDE – 史上功能最强大的桌面环境之一； 开源且免费。19年前，1996年10月14日，德国程序员 Matthias Ettrich 开始了编写这个美观的桌面环境。KDE提供了诸如shell以及其他很多日常使用的程序。今日，KDE被成千上万人在 Unix 和 Windows 上使用。19年----一个对软件项目而言极为漫长的年岁。现在是时候让我们回到最初，看看这一切从哪里开始了。
|
||||
|
||||
K Desktop Environment（KDE）有很多创新之处：新设计，美观，连贯性，易于使用，对普通用户和专业用户都足够强大的应用库。"KDE"这个名字是对单词"通用桌面环境"（Common Desktop Environment）玩的一个简单谐音游戏，"K"----"Cool"。 第一代KDE在双证书授权下使用了有专利的 Trolltech's Qt 框架 （现Qt的前身），这两个许可证分别是 open source QPL(Q public license) 和 商业专利许可证（proprietary commercial license）。在2000年 Trolltech 让一部分 Qt 软件库开始发布在 GPL 证书下; Qt 4.5 发布在了 LGPL 2.1 许可证下。自2009起 KDE 桌面环境由三部分构成：Plasma Workspaces (作Shell)，KDE 应用，作为 KDE Software 编译的 KDE Platform.
|
||||
|
||||
## 各发布版本
|
||||
### Pre-Release – 1996年10月14日
|
||||
|
||||
|
||||
当时名称为 Kool Desktop Environment；"Kool"这个单词在很快就被弃用了。最初，所有KDE的组件都是被单独发布在开发社区里的，他们之间没有任何环绕大项目的组装配合。开发组邮件列表中的第一封通信是发往kde@fiwi02.wiwi.uni-Tubingen.de 的邮件。
|
||||
|
||||
### KDE 1.0 – 1998年7月12日
|
||||
|
||||
|
||||
这个版本受到了颇有争议的反馈。很多人反对使用Qt框架----当时的 FreeQt 许可证和自由软件许可证并不兼容----并建议开发组使用 Motif 或者 LessTif 替代。尽管有着这些反对声，KDE 仍然被很多用户所青睐，并且成功作为第一个Linux发行版的环境被集成了进去。(made its way into the first Linux distributions)
|
||||
|
||||
|
||||
|
||||
1999年1月28日
|
||||
|
||||
一次升级，**K Desktop Environment 1.1**，更快，更稳定的同时加入了很多小升级。这个版本同时也加入了很多新的图标，背景，外观文理。和这些全面翻新同时出现的还有 Torsten Rahn 绘制的全新KDE图标----齿轮前的3个K字母；这个图标的修改版也一直沿用至今。
|
||||
|
||||
### KDE 2.0 – 2000年10月23日
|
||||
|
||||
|
||||
重大更新：_ DCOP (Desktop COmmunication Protocol)，一个端到端的通信协议 _ KIO，一个应用程序I/O库 _ KParts，组件对象模板 _ KHTML，一个符合 HTML 4.0 标准的图像绘制引擎。
|
||||
|
||||
|
||||
|
||||
2001年2月26日
|
||||
|
||||
**K Desktop Environment 2.1** 首次发布了媒体播放器 noatun，noatun使用了先进的模组-插件设计。为了便利开发者，K Desktop Environment 2.1 打包了 KDevelop
|
||||
|
||||
|
||||
|
||||
2001年8月15日
|
||||
|
||||
**KDE 2.2**版本在GNU/Linux上加快了50%的应用启动速度，同时提高了稳定性和 HTML、JavaScript的解析性能，同时还增加了一些 KMail 的功能。
|
||||
|
||||
### KDE 3.0 – 2002年4月3日
|
||||
|
||||
|
||||
K Desktop Environment 3.0 加入了更好的限制使用功能，这个功能在网咖，企业公用电脑上被广泛需求。
|
||||
|
||||
|
||||
|
||||
2003年1月28日
|
||||
|
||||
**K Desktop Environment 3.1** 加入了新的默认窗口（Keramik）和图标样式（Crystal）和其他一些改进。
|
||||
|
||||
|
||||
|
||||
2004年2月3日
|
||||
|
||||
**K Desktop Environment 3.2** 加入了诸如网页表格，书写邮件中拼写检查的新功能；补强了邮件和日历功能。完善了Konqueror 中的标签机制和对 Microsoft Windows 桌面共享协议的支持。
|
||||
|
||||
|
||||
|
||||
2004年8月19日
|
||||
|
||||
**K Desktop Environment 3.3** 侧重于组合不同的桌面组件。Kontact 被放进了群件应用Kolab 并与 Kpilot 结合。Konqueror 的加入让KDE有了更好的 IM 交流功能，比如支持发送文件，以及其他 IM 协议（如IRC）的支持。
|
||||
|
||||
|
||||
|
||||
2005年3月16日
|
||||
|
||||
**K Desktop Environment 3.4** 侧重于提高易用性。这次更新为Konqueror，Kate，KPDF加入了文字-语音转换功能；也在桌面系统中加入了独立的 KSayIt 文字-语音转换软件。
|
||||
|
||||
|
||||
|
||||
2005年11月29日
|
||||
|
||||
**The K Desktop Environment 3.5** 发布加入了 SuperKaramba，为桌面环境提供了易于安装的插件机制。 desktop. Konqueror 加入了广告屏蔽功能并成为了有史以来第二个通过Acid2 CSS 测试的浏览器。
|
||||
|
||||
### KDE SC 4.0 – 2008年1月11日
|
||||
|
||||
|
||||
大部分开组投身于把最新的技术和开发框架整合进 KDE 4 当中。Plasma 和 Oxygen 是两次最大的用户界面风格变更。同时，Dolphin 替代 Konqueror 成为默认文件管理器，Okular 成为了默认文档浏览器。
|
||||
|
||||
|
||||
|
||||
2008年7月29日
|
||||
|
||||
**KDE 4.1** 引入了一个在 PIM 和 Kopete 中使用的表情主题系统；引入了可以让用户便利地从互联网上一键下载数据的DXS。同时引入了 GStreamer，QuickTime，和 DirectShow 9 Phonon 后台。加入了新应用如：_ Dragon Player _ Kontact _ Skanlite – 扫描仪软件，_ Step – 物理模拟软件 * 新游戏: Kdiamond，Kollision，KBreakout 和更多......
|
||||
|
||||
|
||||
|
||||
2009年1月27日
|
||||
|
||||
**KDE 4.2** 被认为是在已经极佳的 KDE 4.1 基础上的又一次全面超越，同时也成为了大多数用户替换旧 3.5 版本的完美选择。
|
||||
|
||||
|
||||
|
||||
2009年8月4日
|
||||
|
||||
**KDE 4.3** 修复了超过10,000个 bugs，同时加入了让近2,000个被用户需求的功能。整合一些新的技术例如：PolicyKit，NetworkManage & Geolocation services 等也是这个版本的一大重点。
|
||||
|
||||
|
||||
|
||||
2010年2月9日
|
||||
|
||||
**KDE SC 4.4** 基础 Qt 4 开框架的 4.6 版本，新的应用 KAddressBook 被加入，同时也是is based on version 4.6 of the Qt 4 toolkit. New application – KAddressBook，Kopete首次发布。
|
||||
|
||||
|
||||
|
||||
2010年8月10日
|
||||
|
||||
**KDE SC 4.5** 增加了一些新特性：整合了 WebKit 库----一个开源的浏览器引擎库，现在也被在 Apple Safari 和 Google Chrome 中广泛使用。KPackageKit 替换了 Kpackage。
|
||||
|
||||
|
||||
|
||||
2011年1月26日
|
||||
|
||||
**KDE SC 4.6** 加强了 OpenGl 的性能，同时照常更新了无数bug和小改进。
|
||||
|
||||
|
||||
|
||||
2011年7月27日
|
||||
|
||||
**KDE SC 4.7** 升级 KWin 以兼容 OpenGL ES 2.0 ，更新了 Qt Quick，Plasma Desktop 中在应用里普遍使用的新特性 1.2万个bug被修复。
|
||||
|
||||
|
||||
|
||||
2012年1月25日
|
||||
|
||||
**KDE SC 4.8**: 更好的 KWin 性能与 Wayland 支持，更新了 Doplhin 的外观设计。
|
||||
|
||||
|
||||
|
||||
2012年8月1日
|
||||
|
||||
**KDE SC 4.9**: 向 Dolphin 文件管理器增加了一些更新，比如加入了实时文件重命名，鼠标辅助按钮支持，更好的位置标签和更多文件分类管理功能。
|
||||
|
||||
|
||||
|
||||
2013年2月6日
|
||||
|
||||
**KDE SC 4.10**: 很多 Plasma 插件使用 QML 重写； Nepomuk，Kontact 和 Okular 得到了很大程度的性能和功能提升。
|
||||
|
||||
|
||||
|
||||
2013年8月14日
|
||||
|
||||
**KDE SC 4.11**: Kontact 和 Nepomuk 有了很大的优化。 第一代 Plasma Workspaces 进入了仅有维护而没有新生开发的软件周期。
|
||||
|
||||
|
||||
|
||||
2013年12月18日
|
||||
|
||||
**KDE SC 4.12**: Kontact 得到了极大的提升。
|
||||
|
||||
|
||||
|
||||
2014年4月16日
|
||||
|
||||
**KDE SC 4.13**: Nepomuk 语义搜索功能替代了桌面上的原有的Baloo搜索。 KDE SC 4.13 发布了53个语言版本。
|
||||
|
||||
|
||||
|
||||
2014年8月20日
|
||||
|
||||
**KDE SC 4.14**: 这个发布版本侧重于稳定性提升：大量的bug修复和小更新。这是最后一个 KDE SC 4 发布版本。
|
||||
|
||||
### KDE Plasma 5.0 – 2014年7月15日
|
||||
|
||||
|
||||
KDE Plasma 5 – 第五代 KDE。大幅改进了设计和系统，新的默认主题 ---- Breeze，完全迁移到了 QML，更好的 OpenGL 性能，更完美的 HiDPI （高分辨率）显示支持。
|
||||
|
||||
|
||||
|
||||
2014年11月11日
|
||||
|
||||
**KDE Plasma 5.1**：加入了Plasma 4里原先没有补完的功能。
|
||||
|
||||
|
||||
|
||||
2015年1月27日
|
||||
|
||||
**KDE Plasma 5.2**：新组件：BlueDevil，KSSHAskPass，Muon，SDDM 主题设置，KScreen，GTK+ 样式设置 和 KDecoration.
|
||||
|
||||
|
||||
|
||||
2015年4月28日
|
||||
|
||||
**KDE Plasma 5.3**：Plasma Media Center 技术预览。新的蓝牙和触摸板小程序；改良了电源管理。
|
||||
|
||||
|
||||
|
||||
2015年8月25日
|
||||
|
||||
**KDE Plasma 5.4**：Wayland 登场，新的基于 QML 的音频管理程序，交替式全屏程序显示。
|
||||
|
||||
万分感谢 [KDE][1] 开发者和社区及Wikipedia 为书写 [概述][2] 带来的帮助，同时，感谢所有读者。希望大家保持自由精神（be free）并继续支持如同 KDE 一样的开源的自由软件发展。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: [https://tlhp.cf/kde-history/](https://tlhp.cf/kde-history/)
|
||||
|
||||
作者：[Pavlo RudyiCategories][a] 译者：[jerryling315](https://github.com/jerryling315) 校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[1]: https://www.kde.org/
|
||||
[2]: https://en.wikipedia.org/wiki/KDE_Plasma_5
|
||||
[a]: https://tlhp.cf/author/paul/
|
||||
@ -0,0 +1,67 @@
|
||||
自定义Ubuntu面板时间日期显示格式
|
||||
================================================================================
|
||||
|
||||
|
||||
尽管设置里已经有一些选项可以用了，这个快速教程会向你展示如何更加深入地自定义 Ubuntu 面板上的时间和日期指示器。
|
||||
|
||||
|
||||
|
||||
在开始之前，在 Ubuntu 软件中心搜索并安装 **dconf Editor**。然后启动该软件并按以下步骤执行：
|
||||
|
||||
**1.** 当 dconf Editor 启动后，导航至 **com -> canonical -> indicator -> datetime**。将 **time-format** 的值设置为 **custom**。
|
||||
|
||||
|
||||
|
||||
你也可以通过终端里的命令完成以上操作：
|
||||
|
||||
gsettings set com.canonical.indicator.datetime time-format 'custom'
|
||||
|
||||
**2.** 现在你可以通过编辑 **custom-time-format** 的值来自定义时间和日期的格式。
|
||||
|
||||
|
||||
|
||||
你也可以通过命令完成：(译注：将 FORMAT_VALUE_HERE 替换为所需要的格式值)
|
||||
|
||||
gsettings set com.canonical.indicator.datetime custom-time-format 'FORMAT_VALUE_HERE'
|
||||
|
||||
以下是参数含义：
|
||||
|
||||
- %a = 星期名缩写
|
||||
- %A = 星期名完整拼写
|
||||
- %b = 月份名缩写
|
||||
- %B = 月份名完整拼写
|
||||
- %d = 按月计日期
|
||||
- %l = 小时 ( 1..12)， %I = 小时 (01..12)
|
||||
- %k = 小时 ( 1..23)， %H = 小时 (01..23)
|
||||
- %M = 分钟 (00..59)
|
||||
- %p = 午别，AM 或 PM， %P = am 或 pm.
|
||||
- %S = 秒 (00..59)
|
||||
- 打开终端键入命令 `man date` 并执行以了解更多细节。
|
||||
|
||||
一些例子：
|
||||
|
||||
自定义时间日期显示格式值：
|
||||
|
||||
**%a %H:%M %m/%d/%Y**
|
||||
|
||||
|
||||
|
||||
**%a %r %b %d or %a %I:%M:%S %p %b %d**
|
||||
|
||||
|
||||
|
||||
**%a %-d %b %l:%M %P %z**
|
||||
|
||||
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://ubuntuhandbook.org/index.php/2015/12/time-date-format-ubuntu-panel/
|
||||
|
||||
作者：[Ji m][a]
|
||||
译者：[alim0x](https://github.com/alim0x)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://ubuntuhandbook.org/index.php/about/
|
||||
@ -0,0 +1,106 @@
|
||||
如何在CentOS上启用Software Collections(SCL)
|
||||
================================================================================
|
||||
|
||||
红帽企业版linux(RHEL)和它的社区版分支——CentOS，提供10年的生命周期，这意味着RHEL/CentOS的每个版本会提供长达10年的安全更新。虽然这么长的生命周期为企业用户提供了更需要的系统兼容性和可靠性，但也存在一个缺点：随着底层的RHEL/CentOS版本接近生命周期的结束，核心应用和运行时环境变得陈旧过时。例如CentOS 6.5，它的生命周期结束时间是2020年11月30日，携带Python 2.6.6和MySQL 5.1.73，以今天的标准来看已经非常古老了。
|
||||
|
||||
另一方面，在RHEL/CentOS上试图手动升级开发工具链和运行时环境存在潜在的可能使系统崩溃，除非所有依赖都被正确解决。通常情况下，手动升级都是不推荐的，除非你知道你在干什么。
|
||||
|
||||
[Software Collections][1](SCL)源出现了，以帮助解决RHEL/CentOS下的这种问题。SCL的创建就是为了给RHEL/CentOS用户提供一种方式以方便、安全地安装和使用应用程序和运行时环境的多个（而且可能更新的）版本，同时避免把系统搞乱。与之相对的是第三方源，它们可能会在已安装的包之间引起冲突。
|
||||
|
||||
最新的SCL提供：
|
||||
|
||||
- Python 3.3 和 2.7
|
||||
- PHP 5.4
|
||||
- Node.js 0.10
|
||||
- Ruby 1.9.3
|
||||
- Perl 5.16.3
|
||||
- MariaDB 和 MySQL 5.5
|
||||
- Apache httpd 2.4.6
|
||||
|
||||
在这篇教程的剩余部分，我会展示一下如何配置SCL源，以及如何安装和启用SCL中的包。
|
||||
|
||||
### 配置SCL源
|
||||
|
||||
SCL可用于CentOS 6.5及更新的版本。要配置SCL源，只需执行：
|
||||
|
||||
$ sudo yum install centos-release-SCL
|
||||
|
||||
要启用和运行SCL中的应用，你还需要安装下列包：
|
||||
|
||||
$ sudo yum install scl-utils-build
|
||||
|
||||
执行下面的命令可以查看SCL中可用包的完整列表：
|
||||
|
||||
$ yum --disablerepo="*" --enablerepo="scl" list available
|
||||
|
||||
|
||||
|
||||
### 从SCL中安装和启用包
|
||||
|
||||
既然你已配置好了SCL，你可以继续并从SCL中安装包了。
|
||||
|
||||
你可以搜索SCL中的包：
|
||||
|
||||
$ yum --disablerepo="*" --enablerepo="scl" search <keyword>
|
||||
|
||||
我们假设你要安装Python 3.3。
|
||||
|
||||
继续，就像通常安装包那样使用yum安装：
|
||||
|
||||
$ sudo yum install python33
|
||||
|
||||
任何时候你都可以查看从SCL中安装的包的列表，只需执行：
|
||||
|
||||
$ scl --list
|
||||
|
||||
----------
|
||||
|
||||
python33
|
||||
|
||||
SCL的优点之一是安装其中的包不会覆盖任何系统文件，并且保证了不会引起系统中其它库和应用的冲突。
|
||||
|
||||
例如，若果在安装python33包后检查默认的python版本，你会发现默认的版本并没有改变：
|
||||
|
||||
$ python --version
|
||||
|
||||
----------
|
||||
|
||||
Python 2.6.6
|
||||
|
||||
如果想使用一个已经安装的SCL包，你需要在每个命令中使用scl命令显式启用它（译注：即想在哪条命令中使用SCL中的包，就得通过scl命令执行该命令）
|
||||
|
||||
$ scl enable <scl-package-name> <command>
|
||||
|
||||
例如，要针对python命令启用python33包：
|
||||
|
||||
$ scl enable python33 'python --version'
|
||||
|
||||
----------
|
||||
|
||||
Python 3.3.2
|
||||
|
||||
如果想在启用python33包时执行多条命令，你可以像下面那样创建一个启用SCL的bash会话：
|
||||
|
||||
$ scl enable python33 bash
|
||||
|
||||
在这个bash会话中，默认的python会被切换为3.3版本，直到你输入exit，退出会话。
|
||||
|
||||
|
||||
|
||||
简而言之，SCL有几分像Python的虚拟环境，但更通用，因为你可以为远远更多的应用启用/禁用SCL会话，而不仅仅是Python。
|
||||
|
||||
更详细的SCL指南，参考官方的[快速入门指南][2]
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://xmodulo.com/enable-software-collections-centos.html
|
||||
|
||||
作者：[Dan Nanni][a]
|
||||
译者：[bianjp](https://github.com/bianjp)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:http://xmodulo.com/author/nanni
|
||||
[1]:https://www.softwarecollections.org/
|
||||
[2]:https://www.softwarecollections.org/docs/
|
||||
@ -0,0 +1,119 @@
|
||||
Linux 教学之教你练打字
|
||||
================================================================================
|
||||
|
||||
|
||||
[Linux 学习系列][1]的所有文章：
|
||||
|
||||
- [Linux 教学之教你练打字][2]
|
||||
- [Linux 教学之物理模拟][3]
|
||||
- [Linux 教学之教你玩音乐][4]
|
||||
- [Linux 教学之两款地理软件][5]
|
||||
- [Linux 教学之掌握数学][6]
|
||||
|
||||
引言：Linux 提供大量的教学软件和工具，面向各个年级段以及年龄段，提供大量学科的练习实践，其中大多数是可以与用户进行交互的。本“Linux 教学”系列就来介绍一些教学软件。
|
||||
|
||||
很多人都要打字，操作键盘已经成为他们的第二天性。 但是这些人中有多少是依然使用两个手指头来快速地按键盘的？即使学校有教我们使用键盘的方法（LCTT 译注：呃。。。），我们也会慢慢地抛弃正确的打字姿势，养成只用两个大拇指玩键盘的习惯。
|
||||
|
||||
下面要介绍的两款软件可以帮你掌控你的键盘，然后你就可以让你的手指跟上你的思维，然后你的思维就不会被打断了。当然，还有很多更炫更酷的软件可供选择，但本文所选的这两款是最简单、最容易上手的。
|
||||
|
||||
### TuxType （或者叫 TuxTyping） ###
|
||||
|
||||
TuxType 是给小孩子玩的。在一些有趣的游戏中，小学生们可以通过完成一些简单的练习来 get “10个手指打字”的新技能。
|
||||
|
||||
Debian 及其衍生版本（包含所有 Ubuntu 衍生版本）的标准软件仓库都有 TuxType，使用下面的命令安装：
|
||||
|
||||
sudo apt-get install tuxtype
|
||||
|
||||
软件开始时有一个简单的 Tux 界面和一段难听的 midi 音乐，幸运的是你可以通过右下角的喇叭按钮把声音调低了。(LCTT译注：Tux 就是那只 Linux 吉祥物，Linus 说它的表情被设计成刚喝完啤酒后的满足感，见《Just For Fun》。)
|
||||
|
||||
|
||||
|
||||
最开始处的两个选项“Fish Cascade”和“Comet Zap”是打字游戏，当你开始游戏时，你需要很投入到这个课程。
|
||||
|
||||
第3个选项为“Lession”,提供40多个简单的课程，每个课程会增加一个字母让你来练习，练习过程中会给出一些提示，比如应该用哪个手指按键盘上的字母。
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
更高级点的，你可以练习输入句子。不知道为什么，句子练习被放在“Options”选项里。（LCTT 译注：句子练习第一句是“The quick brown fox jumps over the lazy dog”，包含了26个英文字母，可用于检测键盘是否坏键，也是练习英文打字的必备良药啊。）
|
||||
|
||||
|
||||
|
||||
这个游戏让玩家打出单词来帮助 Tux 吃到小鱼或者干掉掉下来的流星，训练速度和精确度。
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
除了练习有趣外，这些游戏还可以训练玩家的拼写、速度、手眼配合能力，因为你如果认真在玩的话，必须盯着屏幕，不看键盘打字。
|
||||
|
||||
### GNU typist (gtype) ###
|
||||
|
||||
对于成年人或有打字经验的人来说，GNU Typist 可能更合适，它是一个 GNU 项目，基于控制台操作。
|
||||
|
||||
GNU Typist 也在大多数 Debian 衍生版本的软件库中，运行下面的命令来安装：
|
||||
|
||||
sudo apt-get install gtype
|
||||
|
||||
你估计不能在应用菜单里找到它，只能在终端界面上执行下面的命令来启动：
|
||||
|
||||
gtype
|
||||
|
||||
界面简单，没有废话，直接提供课程内容，玩家选择就是了。
|
||||
|
||||
|
||||
|
||||
课程直截了当，内容详细。
|
||||
|
||||
|
||||
|
||||
在交互练习的过程中，如果你输入错误，会将错误点高亮显示。不会像其他漂亮界面分散你的注意力，你可以专注于练习。每个课程的右下角都有一组统计数据来展示你的表现，如果你犯了很多错误，就可能无法通过关卡了。
|
||||
|
||||
|
||||
|
||||
简单练习只需要你重复输入一些字符，而高阶练习需要你输入整个句子。
|
||||
|
||||
|
||||
|
||||
下图的错误已经超过 3%，错误率太高了，你得降低些。
|
||||
|
||||
|
||||
|
||||
一些训练用于完成特殊目标，比如“平衡键盘训练（LCTT 译注：感觉是用来练习手感的）”。
|
||||
|
||||
|
||||
|
||||
下图是速度练习。
|
||||
|
||||
|
||||
|
||||
下图是要你输入一段经典文章。
|
||||
|
||||
|
||||
|
||||
如果你想练习其他语种，操作一下命令行参数就行。
|
||||
|
||||
|
||||
|
||||
### 总结 ###
|
||||
|
||||
如果你想练练自己的打字水平，Linux 上有很多软件给你用。本文介绍的两款软件界面简单但内容丰富，能满足绝大多数打字爱好者的需求。如果你正在使用、或者听说过其他的优秀打字练习软件，请在评论栏贴出来，让我们长长姿势。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.maketecheasier.com/learn-to-type-in-linux/
|
||||
|
||||
作者：[Attila Orosz][a]
|
||||
译者：[bazz2](https://github.com/bazz2)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.maketecheasier.com/author/attilaorosz/
|
||||
[1]:https://www.maketecheasier.com/series/learn-with-linux/
|
||||
[2]:https://www.maketecheasier.com/learn-to-type-in-linux/
|
||||
[3]:https://www.maketecheasier.com/linux-physics-simulation/
|
||||
[4]:https://www.maketecheasier.com/linux-learning-music/
|
||||
[5]:https://www.maketecheasier.com/linux-geography-apps/
|
||||
[6]:https://www.maketecheasier.com/learn-linux-maths/
|
||||
@ -0,0 +1,99 @@
|
||||
Linux 教学之两款地理软件
|
||||
================================================================================
|
||||
|
||||
|
||||
[Linux 学习系列][1]的所有文章：
|
||||
|
||||
- [Linux 教学之教你练打字][2]
|
||||
- [Linux 教学之物理模拟][3]
|
||||
- [Linux 教学之教你玩音乐][4]
|
||||
- [Linux 教学之两款地理软件][5]
|
||||
- [Linux 教学之掌握数学][6]
|
||||
|
||||
引言：Linux 提供大量的教学软件和工具，面向各个年级段以及年龄段，提供大量学科的练习实践，其中大多数是可以与用户进行交互的。本“Linux 教学”系列就来介绍一些教学软件。
|
||||
|
||||
地理是一门有趣的学科，我们每天都能接触到，虽然可能没有意识到，但当你打开 GPS、SatNav 或谷歌地图时，你就已经在使用这些软件提供的地理数据了；当你在新闻中看到一个国家的消息或听到一些金融数据时，这些信息都可以归于地理学范畴。Linux 提供了很多学习地理学的软件，可用于教学，也可用于自学。
|
||||
|
||||
### Kgeography ###
|
||||
|
||||
在多数 Linux 发行版的软件库中，只有两个与地理有关的软件，两个都属于 KDE 阵营，或者说都属于 KDE 教育项目。Kgeopraphy 使用简单的彩色编码图来绘制被选中的国家。
|
||||
|
||||
Ubuntu 及衍生版在终端执行下面命令安装软件：
|
||||
|
||||
sudo apt-get install kgeography
|
||||
|
||||
界面很简单，给你一个选择界面，你可以选择不同的国家。
|
||||
|
||||
|
||||
|
||||
点击地图上的某个区域，界面就会显示这个区域所在的国家和首都。
|
||||
|
||||
|
||||
|
||||
以及给出不同的测试题来检测你的知识水平。
|
||||
|
||||
|
||||
|
||||
这款软件以交互的方式测试你的地理知识，并且可以帮你为考试做好充足的准备。
|
||||
|
||||
### Marble ###
|
||||
|
||||
Marble 是一个稍微高级一点的软件，无需 3D 加速就能提供全球视角。
|
||||
|
||||
|
||||
|
||||
在 Ubuntu 及衍生版的终端输入下面的命令来安装 Marble：
|
||||
|
||||
sudo apt-get install marble
|
||||
|
||||
Marble 专注于地图绘制，它的主界面就是一张地图。
|
||||
|
||||
|
||||
|
||||
你可以选择不同的投影方法，比如球状投影和麦卡托投影（LCTT 译注：把地球表面绘制在平面上的方法），在下拉菜单里你可以选择平面视角或外部视角，包括 Atlas 视角，OpenStreetMap 提供的成熟的离线地图，
|
||||
|
||||
|
||||
|
||||
以及卫星视角（由 NASA 提供），
|
||||
|
||||
|
||||
|
||||
以及政治上甚至是历史上的世界地图。
|
||||
|
||||
|
||||
|
||||
除了有包含不同界面和大量数据的离线地图，Marble 还提供其他信息。你可以在菜单中打开或关闭不同的离线 info-boxes
|
||||
|
||||
|
||||
|
||||
和在线的 online services。
|
||||
|
||||
|
||||
|
||||
一个有趣的在线服务是维基百科，点击下 Wiki 图标，会弹出一个界面来展示你选中区域的详细信息。
|
||||
|
||||
|
||||
|
||||
这款软件还提供定位追踪、路由规划、位置搜索和其他有用的功能。如果你喜欢地图学，Marble 可以让你长时间享受探索和学习的乐趣。
|
||||
|
||||
### 总结 ###
|
||||
|
||||
Linux 提供大量优秀的教育软件，当然也包括地理学科。本文介绍的两款软件可以帮你学到很多地理知识，并且你可以以一种好玩的人机交互方式来测试你的知识量。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.maketecheasier.com/linux-geography-apps/
|
||||
|
||||
作者：[Attila Orosz][a]
|
||||
译者：[bazz2](https://github.com/bazz2)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]:https://www.maketecheasier.com/author/attilaorosz/
|
||||
[1]:https://www.maketecheasier.com/series/learn-with-linux/
|
||||
[2]:https://www.maketecheasier.com/learn-to-type-in-linux/
|
||||
[3]:https://www.maketecheasier.com/linux-physics-simulation/
|
||||
[4]:https://www.maketecheasier.com/linux-learning-music/
|
||||
[5]:https://www.maketecheasier.com/linux-geography-apps/
|
||||
[6]:https://www.maketecheasier.com/learn-linux-maths/
|
||||
Loading…
Reference in New Issue
Block a user