Sending emails securely is needed for certain situations, such as sending my bank account to my wife, giving my account password to my close friend for a while. How to send it? Regarding the recent US PRISM program, it is an important issue. Seeing your solution, a few of my own popped up. Here are
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Category: Tutorial
Excerpt in homepage, category, tag and author pages for WordPress theme Twenty Thriteen
Posted onExcerpt in homepage, category, tag and author pages for WordPress theme Twenty Thriteen. Also add the “read more” link after the excerpt. The patch: diff –git a/wp-content/themes/twentythirteen/content.php b/wp-content/themes/twentythirteen/content.php index 4f61b22..53b4686 100644 — a/wp-content/themes/twentythirteen/content.php +++ b/wp-content/themes/twentythirteen/content.php @@ -30,7 +30,7 @@ </div><!– .entry-meta –> </header><!– .entry-header –> – <?php if ( is_search() ) : // Only display
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Add the jane street opam repository
Posted onHow to add the jane street opam repository is introduced here. Here, we assume the branch to add is core-branch. You may need to replace the core-branch with the branch you need. $ git clone -b core-branch https://github.com/janestreet/opam-repository.git $ opam repo add js opam-repository Or, directly add the remote branch as an opam repository. $
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How to import OCaml libraries
Posted onHow to import 3rd party libraries (e.g. not standard libraries) in OCaml? An answer by Gabriel Scherer on how to import Batteries is just great and answers this question with much information. Although it is for Batteries, the method is general. The OCaml compiler (or toplevel, etc.) will find with no additional information only the
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Redis Architecture, consistency model, etc.
Posted onTechnical discussions on Redis. Redis internal documentation: http://redis.io/topics/internals Redis manifesto, the philosophy behind Redis: http://oldblog.antirez.com/post/redis-manifesto.html Redis Architecture: Overview Of Redis Architecture Redis data model and eventual consistency: http://antirez.com/news/36
Max array length in OCaml
Posted onWhat’s the max array length in OCaml. You can check it by: # Sys.max_array_length;; On 64-bit machine: # Sys.max_array_length;; – : int = 18014398509481983 On a 32-bit machne: # Sys.max_array_length;; – : int = 4194303 This is due to the memory representation of arrays. 64 Bit machines are better here. And AFAIK, OCaml was developed
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Vim Regular Expressions Tutorials
Posted onGood tutorials on Vim regular Expressions. Vim Regular Expressions: http://www.softpanorama.org/Editors/Vimorama/vim_regular_expressions.shtml Another good one in Chinese: http://www.study-area.org/tips/vim/Vim-10.html
Find out the number of CPU cores on Linux
Posted onHow to find out the number of CPU cores on a Linux host. Use the command nproc. $ nproc nproc – print the number of processing units available: man page of nproc.
Installing Fedora 19, Error “you have not created a bootloader stage1 target device”
Posted onInstalling Fedora 19, Error “you have not created a bootloader stage1 target device” . It seems appear from Fedora 15: http://forums.fedoraforum.org/showthread.php?t=271743 This can be solved by adding noefi nogpt to the kernel parameters when booting the Linux for installation in grub as follows. Note: the “_” between nogpt and root is the cursor, not the
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How to find out and change the storage engine of tables in MySQL
Posted onHow to find out and change the storage engine of tables in MySQL databases? Find out the storage engine of a table in a database: SELECT ENGINE FROM information_schema.TABLES WHERE TABLE_SCHEMA = ‘database’ AND TABLE_NAME = ‘table’ Change the storage engine of a table: ALTER TABLE table ENGINE = type type can be innodb or
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How to change the maximum execution time and memory size allowed for PHP
Posted onI see this message in the error log of httpd: PHP Fatal error: Maximum execution time of 30 seconds exceeded in and PHP Fatal error: Allowed memory size of 268435456 bytes exhausted How to change them to a longer and larger value? To change the allowed maximum memory usage of PHP: Set memory_limit = 256M
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How to change strings in MySQL tables
Posted onHow to change strings in MySQL tables? e.g. I want to change domain.com to www.domain.com. Use the REPLACE functions of MySQL: http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_replace One example is like this: UPDATE table SET field = REPLACE(field, ‘domain.com’, ‘www.domain.com’) WHERE field LIKE ‘%domain.com%’ The WHERE clause is not needed but can make execution faster.
HP Printer with Fedora Linux 19
Posted onHow to use HP Printer connected with USB on Fedora Linux 19. Install these packages and it may ask you to download and install other plugins. Without these packages, my printer does work. # yum install hplip hplip-gui hpijs May also need to run: # hp-plugin to install plugins for the HP printer. This plays
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PDF annotation tools on Linux
Posted onWhat are good PDF annotation tools on Linux? Preferring saving the annotation in the PDF instead of separate files or images. I find the best solution may be wine + Foxit Reader. Foxit Reader can annotate PDF files and save them. It works very well on wine. Steps to install them: Install wine # yum
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How to install WordPress on Fedora 19
Posted onHow to install the latest WordPress on a newly installed Fedora 19? Thanks! First, install the LAMP (you already have ‘L’) stack: # yum install httpd php php-mysql mysql-server php-gd and start these services: # systemctl start mysqld.service httpd.service Then, install WordPress on the LAMP stack following the tutorials on the Web. Two good ones
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How to repair tables database by backup
Posted onHow to repair tables database by backup Is this possible? Please explain how to repair. and thanks This post may help: https://www.systutorials.com/qa/300/how-to-repair-a-mysql-table thanks dear Zhiqiang Ma
Online image editor like Photoshop
Posted onIs there any online image editor that has the basic functions of Photoshop. Basic editing of the image should be enough. pixlr is a very good tools for this purpose: http://pixlr.com/ It works great for me.
gnuplot and ps2epsi do not work on Fedora 19
Posted onI find that gnuplot and ps2epsi do not work on Fedora 19. The same packages/scripts work for me on old installations on Fedora 17. I find this line is printed out multiple times: Fontconfig warning: “/etc/fonts/conf.d/50-user.conf”, line 14: reading configurations from ~/.fonts.conf is deprecated. I even tried an older version of gnuplot (4.2 patchlevel 6).
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Trap Ctrl-C in a Bash script
Posted onHow to trap Ctrl-C in a Bash script? The piece of code: # trap ctrl-c and call ctrl_c() trap ctrl_c INT function ctrl_c() { echo echo “Ctrl-C by user” # do the jobs exit }
How to choose the number of mappers and reducers in Hadoop
Posted onHow to choose the number of mappers and reducers in Hadoop to get good job performance? The Hadoop Wiki gives a discussion on this: http://wiki.apache.org/hadoop/HowManyMapsAndReduces Some valuable points: About the number of Maps: The number of maps is usually driven by the number of DFS blocks in the input files. Although that causes people to
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