How to get the directory path and file name from a absolute path in C on Linux? For example, with “/foo/bar/baz.txt”, it will produce: “/foo/bar/” and “baz.txt”. You can use the APIs basename and dirname to parse the file name and directory name. A piece of C code: #include <libgen.h> #include <string.h> char* local_file =
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Category: Tutorial
Multi-connection multi-part file downloading tools on Linux
Posted onIs there any good multi-connection multi-part file downloading tools on Linux? wget is great but can only make 1 connection for 1 file. Sometimes, it is too slow on some networks. I use aria2 which supportsmMulti-connection download. aria2 can download a file from multiple sources/protocols and tries to utilize your maximum download bandwidth. Really speeds
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Convention of error codes on Linux and Windows
Posted onWhat’s the error code conventions on Linux and Windows? Linux and Windows use 0 to indicate that the operation is successful and an integer that is larger than 0 for some errors. Linux System Error Codes On Linux, the system error codes is defined in 2 headers which you can find on your own box:
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How to print out text with line numbers in Linux
Posted onHow to print out a plain text file with line numbers in Linux? Use the nl command: nl text-file Find options in the nl manual.
How to print a plain text file to printers from a terminal in Linux
Posted onHow to quickly print a plain text file to printers from a terminal in Linux? You can also use enscript: enscript – convert text files to PostScript, HTML, RTF, ANSI, and overstrikes https://www.systutorials.com/docs/linux/man/1-enscript/ enscript text-file The lp command can print a plain text file to a printer. My favorite command: cat text-file | lp -o
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Ghostscript reports “Unrecoverable error: stackunderflow in .setdistillerparams”
Posted onWith the command -dPDFSETTINGS=/print for ps2pdf, I got: GPL Ghostscript 9.10: Set UseCIEColor for UseDeviceIndependentColor to work properly. Unrecoverable error: stackunderflow in .setdistillerparams make: *** [pdf-print] Error 255 How to fix it? I use this workaround: ps2pdf -dColorConversionStrategy=/LeaveColorUnchanged -dPDFSETTINGS=/printer psfile.ps from this. An alternative is to use -dPDFSETTINGS=/prepress.
How to add a space between the line numbers and text content in Emacs?
Posted onI use Emacs in console. The linum-mode displays the line numbers just well. However, in the console, there is no space between the line numbers and the text content, which makes it a little messy some times. How to add a space between the line numbers and text content in Emacs? If you are using
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How to export and import message filters of Thunderbird
Posted onI have several installation of Thunderbird under Linux to check/send emails using IMAP email servers. I use filters extensively to manage my emails. How to export and import message filters of Thunderbird so that I can synchronize the rules on several installations? About message filters in Thunderbird (More at http://kb.mozillazine.org/Filters_(Thunderbird)): Filters are account specific, there
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Alternatives to goto in bash
Posted onAs we know: There is no goto statement support in bash. goto is useful for certain situations, especially for debugging. So, is there any alternative mechanisms to goto in bash? Robert Copeland gave an interesting hacking to this problem: http://bobcopeland.com/blog/2012/10/goto-in-bash/ The idea is like the self-modifying code. But the difference is to generate a piece
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How to back up a complete IMAP account?
Posted onI have a large IMAP email account which contains many emails in a rich structure of directories. How to back up the whole IMAP account to my local computer? The requirements: Automatically downloading these files. There are many directories, and copying-pasting emails will take too much time. Keep the directory structures which are used to
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How to make Emacs start up faster?
Posted onI use Emacs in consoles and start Emacs frequently (like check a file, edit it, close it and loop). However, Emacs seems take some time to start up especially some modes/extensions are used. How to make Emacs start up faster? I summarize my solution at this post: Making Emacs Startup Faster. The key is to
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How to make xterm display Chinese characters?
Posted onHow to make xterm display Chinese characters? It just displays some small rectangles for Chinese characters. First, the settings for some old X programs like xterm is in ~/.Xresources. And it takes effect after the X server restarts, or you can manually load the settings by xrdb -merge ~/.Xresources Second, the Chinese or similar fonts
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Directly SSH to hosts using internal IPs through the gateway
Posted onWe have many hosts with internal IPs like 10.0.3.* behind a gateway, say gateway.example.org. The hosts with internal IP connect to the Internet through the gateway. How to directly SSH to hosts using internal IPs through the gateway? Here is the solution: Directly SSH to Hosts with LAN IPs Through the Gateway
How to change the default text editor on Linux
Posted onOn Linux, a default editor is used for text editing such as crontab -e or git commit. How to change it to the editor of my own choice? The default editor is indicated by the EDITOR environment variable. You can set this environment variable to set the default editor. For example, set it to emacs
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How to set options for scala in sbt
Posted onIn sbt, I found this message printed out by the scala compiler: [warn] there were 1 deprecation warning(s); re-run with -deprecation for details [warn] one warning found The question is, how to add options (-deprecation here) to the scala compiler in sbt? You can use this inside the sbt console: set scalacOptions += “-deprecation”
How to efficiently take screenshot on Windows 7
Posted onI am tired of the non-efficient “Print Screen” -> Paste in Paint -> Save way. How to efficiently take screenshot on Windows 7? On Windows 7 and later ones, the “Snipping Tool” is handy. Press the “Win” key and input “snipping tool”. The tool will appear in the menu. You can select the whole window,
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Programming language popularity indices?
Posted onAny good programming language popularity indices? Those are interesting ones: TIOBE Indexhttp://www.tiobe.com/index.php/content/paperinfo/tpci/index.html The RedMonk Programming Language Rankings: January 2014 This ranking is published as blog posts. So no persistent homepage found yet. The January 2014 version is: http://redmonk.com/sogrady/2014/01/22/language-rankings-1-14/ Programming Language Popularityhttp://langpop.com/
How to `cut` a String Using a String as the Delimiter in Bash?
Posted onIs is possible to cut in Linux using a string as the delimiter? cut –delimiter=”delim” -f 1,3 cut reports: cut: the delimiter must be a single character The most closest solution that I find is using awk/gawk: awk -F ‘delim’ ‘{print $1; print $3}’ From the manual: -F fs –field-separator fs Use fs for the
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WordPress theme TwentyFourteen interfere with AddThis Welcome Bar
Posted onThe AddThis welcome bar will make a empty gap on top of the WordPress webpage with the TwentyFourteen wordpress theme. Is there a fix for it? You will find AddThis will add this div to the webpage: <div class=”addthis_bar_placeholder” style=”height: 46px;”></div> which cause the problem. A little trick that works is to set that div’s
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How to install drivers for TL-WN725N v2 USB wireless adapter on Fedora 19
Posted onI had a TP-Link TL-WN725N v2 USB wireless adapter. But it seems the kernels in Fedora 19 have not yet included drivers for it. How to install drivers for TL-WN725N v2 on Fedora 19? The driver is under development. You can find the source here and in the drivers/staging in the Linux kernel. If you
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