Generating RSA Private and Public Key Pair in Go Lang?

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How to generate a pair of RSA private and public key in Go lang? Go lang has a rich set of standard libraries. Using Go’s standard libraries, we can generate RSA private and Public keys. The Crypto standard libraries in Go lang Go lang standard libraries has a rich set of cryptography functions. Here are
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File system Inode flags: difference between FS_IOC_GETFLAGS and FS_IOC_FSGETXATT

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What is the difference between FS_IOC_GETFLAGS and FS_IOC_FSGETXATTR ioctl commands? What flags do both return? The comment in fs.h is clear enough to explain itself. In short, FS_IOC_GETFLAGS was for ext2/ext3 only, and FS_IOC_FSGETXATTR is a generic FS level interface. Full comment as follows for your reference (source): /* * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
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How to encode spaces in curl GET request URL on Linux?

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The problem is like this: I would like to send a GET request using curl and the content has spaces, such as curl “http://example.com/send?msg=hello world” The space and the “world” will be left away if this command is executed directory on Linux. How to encode spaces in curl request URL? You can use the –date-urlencode
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Cannot connect QEMU guest os with vncviewer

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The question is as follows. harry@debian:~/workshop1/qemu_test/version1/test$ qemu-system-x86_64 -hda qcow2.img -cdrom domU-x86_64-FS.img -boot d -m 1024 VNC server running on `::1:5900′ harry@debian:~/workshop1/qemu_test/version1/test$ vncviewer 127.0.0.1:1 vncviewer: ConnectToTcpAddr: connect: Connection refused Unable to connect to VNC server Solution (add -vnc parameter for qemu-system-x86_64): harry@debian:~/workshop1/qemu_test/version1/test$ qemu-system-x86_64 -hda qcow2.img -cdrom domU-x86_64-FS.img -boot d -m 1024 -vnc 127.0.0.1:2 harry@debian:~/workshop1/qemu_test/version1/test$ vncviewer 127.0.0.1:2
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Plain text file pipelined to Linux mailx turns to “Content-Type: application/octet-stream” (an attachment)

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Plain text file pipelined to Linux mailx turns to “Content-Type: application/octet-stream” which is recognized as an attachment by some email client. The command is like this: $ cat log.txt | mail -s “Updated log file” -r “from@example.com” “to@example.com” I expect it to be: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit But it turns out to be: Content-Type:
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A Beginners’ Guide to x86-64 Instruction Encoding

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The encoding of x86 and x86-64 instructions is well documented in Intel or AMD’s manuals. However, they are not quite easy for beginners to start with to learn encoding of the x86-64 instructions. In this post, I will give a list of useful manuals for understanding and studying the x86-64 instruction encoding, a brief introduction
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Reference: Special HTML Characters

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HTML supports many characters/symbols such as mathematical symbols, and currency symbols. They are not present on a normal keyboard. And some of these characters may have special meanings for formatting text. To add such characters / symbols to an HTML text, you can use an HTML entity name or an entity number in decimal or
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ASCII Table and ASCII Code

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This post gives the ASCII table and ASCII code with ASCII control characters and ASCII printable characters and a tool to convert ASCII codes to ASCII characters. Introduction to ASCII table and ASCII code ASCII stands for American Standard Code for Information Interchange. An ASCII code is the numerical representation of a character since computers
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Speeding Up the Site With Apache GZIP Compression

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We can speed up the site with compression while save bandwidth at the same time. As most of the modern browsers support gzip encoding, we can set it up to let the users enjoy faster speed. The Apache mod_deflate is easy to set up and standard. It compress the content on the fly. We can
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How to Change the Site’s Default 404 Error Not Found Page

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The 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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Vim as Thunderbird’s External Editor in Linux

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Vim is an excellent editor which I use every day. Thunderbird is a nice email application. However, Thunderbird’s integrated editor is not efficient enough to a Vim user. Why not use Vim as Thunderbird’s editor? In this tutorial, we will introduce how to integrate Vim with Thunderbird together in Linux. Install the “External Editor” Thunderbird
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解决FAT32文件系统分区中文文件名在Linux下显示乱码

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升级到Fedora 11后,使用以前的fstab自动挂载我的fat32分区居然发现我的fat32文件系统中的中文文件名显示为乱码。 找了下相关资料发现是iocharset的问题: iocharset=name — Character set to use for converting between the encoding is used for user visible filename and 16 bit Unicode characters. Long filenames are stored on disk in Unicode format, but Unix for the most part doesn’t know how to deal with Unicode. By default, FAT_DEFAULT_IOCHARSET setting is used. Windows文件系统的长文件名是用16位的Unicode存储的, 而Linux文件系统不支持16位的字符,所以需要在两者之间转换,这就是iocharset要完成的功能。
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Colossus: Successor to the Google File System (GFS)

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Colossus is the successor to the Google File System (GFS) as mentioned in the paper on Spanner at OSDI 2012. Colossus is also used by spanner to store its tablets. The information about Colossus is slim compared with GFS which is published in the paper at SOSP 2003. There is still some information about Colossus
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