Compression is a simple way to speed up the site. PHP’s gzip compression is excellent. And using it is very convenient: Simply put these codes before any HTML content at the beginning of the PHP script: <?php if (substr_count($_SERVER[‘HTTP_ACCEPT_ENCODING’], ‘gzip’)) ob_start(“ob_gzhandler”); else ob_start(); ?> In WordPress, the suitable position for these codes is the beginning
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How to Read File into String in PHP
Posted onRead content of a file to string (in this example, we echo it): // Get text from file function get_text($text_filename) { if ($text_filename != “”) { $text = “”; $text_file = fopen($text_filename, “r”); while (!feof($text_file)) { $text = $text . fgets($text_file, 4096); } fclose($text_file); if ( $text != “” ) { echo $text; } }
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Get the Number of All Posts in WordPress
Posted onUse the wp_count_posts() function to get the posts count. The code: <?php $count_posts = wp_count_posts(); $count_pages = wp_count_posts(‘page’); echo “<li><a href=” . get_option(‘home’) . “>”; echo $count_posts->publish . ” Posts, ” . $count_pages->publish . ” Pages”; echo “</a></li>” ?>
How to Redirect a Page with HTTP 301 in PHP
Posted onHTTP 301 Redirect is an SEO friendly way to redirect readers to a page’s new location. There are a lot of benefits of using HTTP 301 Redirect. These benefits can be found in the htaccess method post. htaccess or PHP can be both used for sending 301 redirects. The htaccess method can be found in
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Friendly WordPress Navigation Using Page Numbers Instead of Next and Previous Links
Posted onThe navigation will be more user friendly with page numbers instead of next and previous links since users can navigate much quicker to the page they want to see especially when there are a lot of pages. It is also good method for SEO (Search Engine Optimization) because it creates a tighter inner link structure.
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Using noindex Meta Tag in WordPress to Prevent Search Engines Indexing Categories, Tags and Archives
Posted onWordPress may show “duplicate” content which may potentially confuse search engines. Duplicate content won’t hurt much, unless it is spam or keyword stuffing, as said by Matt Cutts, and Google may just ignore the duplicate content. However, instead of letting the search engines decide which pages of the duplicate ones are important, we may only
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Change WordPress’s Excerpt Length
Posted onThe default excerpt length of WordPress is 55 words. Some one like me may want to change the excerpt length. I like the have a smaller excerpt length for the homepage. WordPress provides a interface for changing the default excerpt length. The method is very simple and easy. Put these codes into the function.php file
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Put the Categories, Archives and All Posts into Pages
Posted onI prefer putting pages that contains all the categories, archives and even all the posts in one page to putting these links in the side bar. Actually, most of time it needn’t to stay on every pages. And if it is in the side bar, the search engine will see these links in every page
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How to Redirect Old Domain to New Domain Using htaccess Redirect
Posted onI want to move the sub domain blog.pkill.info to systutorials.com permanently. I can manage all the pages I want to post using WordPress. Changing domain in a bad way is dangerous. Put a page the tell the reader that the site is moved to a new domain is very unfriendly to the user and also
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Use Excerpt in Index, Category, Tag and Arhieve Pages for WordPress
Posted onBy default, all of the content of the post is shown in index, category, tag, archive and search pages. This is duplicate contents which may cause search engine penalty. The better way is using excerpt in index, category, tag and arhieve pages. By doing this the duplication can be avoided and the blog is optimized.
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How to Change the Site’s Default 404 Error Not Found Page
Posted onThe apache’s default “404 Error not found” page seems ugly. And may some hosting service put theire ads in it. We can add some entry in .htaccess to change the defualt 404 error page. This method can also be used for some other error codes. A list of the server returned codes can be found
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Using “META” Tag in HMTL HEAD to Redirect Pages
Posted onIt is quite simple to redirect pages using the “meta” tag in HTML head, I just give the example to redirect the page to https://www.systutorials.com after 1 second. <html> <head> <meta http-equiv=”Refresh” content=”1; url=https://www.systutorials.com/”> </head> <body> This page is redirected to: <a href=”https://www.systutorials.com/”>systutorials.com</a>.<br /> </body> </html>
Yum Using DVD as Package Repository
Posted onWe introduce the method to use DVD as the package repository for yum. In this post, we use CentOS 5 as the example. 1) Modify /etc/yum.repos.d/CentOS-Base.repo Delete baseurls in [Base] baseurl by add ‘#’ at the beginning of the lines Then add a line at the end: baseurl=file:///media/CentOS_5.0_Final ‘file://’ means this is a local directory.
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Script: Checking Alive Servers from a Server List
Posted onWith a list of servers, it is common that one or more are down or crash. Lots cluster management tools can detect the aliveness of servers. However, it can be easily done with ping with a Bash script. I summarize the script that I used and share it here: check-alive-server.sh. Usage: usage: ./check-alive-server.sh file Each
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Script: Running Commands on a List of Servers
Posted onI frequently run some commands/scripts on a batch of servers whose IPs are already collected in a file. I usually use a simple loop and call the ssh to run these commands remotely and automatically. This operation, however, is common and can be abstracted into a separate script. Here is the script that I come
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Script: Shutting Down All Xen VMs on a Server
Posted onShutting down servers is a common operations for managing a cluster. However, if this server is configured to a Xen Dom0 and has Xen VMs (DomUs), the VMs should be shutdown first to avoid data lost on these VMs. xm supports a -a option to shutdown all VMs: # xm shutdown -a Add the -w
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How to install Scala on Linux
Posted onHow to install Scala on Fedora Linux How to install Scala on Fedora Linux: This tutorial introduces how to install Scala 2.9.2 on 64-bit Fedora Linux 17. There are some changes needed to make scala work on Fedora Linux 17. Please check it out in the answer. Continue reading: How to install Scala on Fedora
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Emacs Tips and Howtos
Posted onWith Emacs, I feel happy. I love the rich functions of Emacs, such as compiling, quickly jumping to the lines with compilation error and debugging with gdb, and more. I ever wrote small tips posts about Emacs before. But it is a good idea to put them together and keep adding new ones. Here comes
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Viewing XPS Files in Linux
Posted onXPS files is a format from MS on Windows. Evince can view some XPS files, but fails to view some. To view XPS files generated on Windows on a Linux system, we can use mupdf. It works very well. I like it much especially in the situation that Evince fails to open the XPS file.
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How to Generate and Apply Patches using diff and patch on Linux
Posted on`diff` and `patch` are tools to create patches and apply patches to source code, which is widely used in the open-source world, such as Linux kernel and application. patch: applying patches To apply a patch to a single file: $ patch < foo.patch If the foo.patch does not identify the file the patch should be
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