Grub2: How to boot Fedora to an old kernel? The old kernel is a submenu under “Advanced options for Fedora”. It is not shown if I follow the instruction that # grep menuentry /boot/grub2/grub.cfg | cut -d “‘” -f2. The old kernel in grub2 is in a submenu entry in a menu. The key is…
How to set Chrome RSS Subscription Extension so that I can subscribe to RSS feed using Feedly? Both tools are great and it will be better to combine them together. The link in feedly to subscribe a RSS feed (e.g. https://www.systutorials.com/b/feed/ ) is: http://www.feedly.com/home#subscription/feed/https://www.systutorials.com/b/feed/ We can replace the RSS feed URL with a %s in…
I frequently hear that cin is significantly slower than scanf in C++. Is this true? And how to improve the efficiency of cin? It is really nice to use most of time. One discussion about that cin is very slow is here: http://apps.topcoder.com/forums/?module=Thread&threadID=508058&start=0&mc=7 In short: cin is not always slower (can be faster actually, see…
How to import a source file to OCaml’s toplevel? Say, I want to use a function implemented in a source file in the toplevel. #use “file-name”;; Read, compile and execute source phrases from the given file. This is textual inclusion: phrases are processed just as if they were typed on standard input. The reading of…
I am writing a OCaml program but want to call some C functions provided in some source code or library. How to achieve this? Is there any good tutorials on this? A very good tutorial that is easy to follow and understand: How to wrap C functions to OCaml. A comprehensive reference manual: Chapter 19…
How to set Google Chrome’s proxy settings in command line on Linux? I am using Google Chrome on Linux and start it by google-chrome. How can I set the proxy using the command line? It tell me that my desktop is not supported but I can set the proxy in command line. Use the –proxy-server…
How to restore a Gnome 3 session? Which means: opening all the programs running last time when I log out in Gnome 3. If your purpose is to automatically start programs after logging in Gnome, another possible method is using the autostart script: https://www.systutorials.com/qa/119/how-to-write-a-autostart-script-for-gnome Run gnome-session-properties. In the “Options” tab, select “Automatically remember running applications…
How to add Google Custom Search to Question2answer? I do not want to create / edit / use a advanced theme. What I prefer is a plugin to replace the default search module with Google Custom Search. Thanks! Check out the Google Custom Search plugin: Google Custom Search plugin This site use it and it…
How to Sync the Contacts in My iPhone with Google Gmail Account? To sync your Google contacts, one good method is using CardDAV. You’ll be able to edit, add, and remove contacts from your device and keep them in sync with your Google Gmail account. It is straightforward: Open the Settings application on your device….
What I want is to just restart Gnome 3 only and not to close and reopen the programs running. Thanks a lot! Just run r in Gnome 3’s “Run command” Box: Alt + F2, then enter r and hit Enter. Gnome 3 will restarts itself only.
I come across some closed source software that only provides .deb packages. Fedora manages packages with rpm/yum. How to install the .deb packages on Fedora? Alien is a tool to convert .deb package to .rpm package: http://joeyh.name/code/alien/ In latest Fedora, the tool alien is in Fedora’s repository. You can use dnf to install the package….
iPhone has the touch screen. Is is possible to turn my iPhone to a wireless mouse on Linux? Use the WiFi Mouse app/server: http://wifimouse.necta.us/ First, install the WiFi Mouse app on you iPhone: https://itunes.apple.com/app/id591076411?mt=8 Second, install the WiFi Mouse server downloaded from http://wifimouse.necta.us/ If you are using Fedora Linux, you need to convert the .deb…
How To Find Out When Photos in The iPhone Were Taken? The default viewer in iPhone seems do not show these information. The iPhone has no native mechanism to see the photo taken date information. However there is the information. You need a 3’rd party application to view the EXIF data (time taken, GPS coordinates,…
How to add an existing user to an existing group in Linux? We can use usermod to change/add user group for users. # usermod -a -G group_name user_name -a, –append Add the user to the supplementary group(s). Use only with the -G option. -G, –groups GROUP1[,GROUP2,…[,GROUPN]]] A list of supplementary groups which the user is…
How to statically compile C and C++ projects? The compiled executable should lead no dynamical library during execution. I use gcc/g++ to compile the projects. Check this post: Statically Linking C and C++ Programs on Linux with gcc.
How to add the social share icons to q2a as shown in this site? This site uses the Question2Answer Share plugin: https://github.com/NoahY/q2a-share After installing the plugin by downloading and copying the directory for the plugin to the qa-plugin directory, you can select the networks to share to in ‘Admin -> Plugins’. I see. Thanks!
After checking the Question2Answer pages’ HTML code, I find that the main div comes after the side panel. How to revert the position of the main div and side panel div? Makes the main content come first in the HTML. You can change the displaying order by overwriting the body_content() function in the theme (that…
In Question2Answer, how to enable Sina Weibo and Tencent QQ account log in? Use the Social Plugin for Sina Weibo and Tencent QQ (in Chinese): http://q2achina.sinaapp.com/blog/archives/22/ The websites to apply for the app: Weibo: http://open.weibo.com/ QQ: http://connect.qq.com/
I like the Markdown editor whick is widely used (e.g. This site) and very convenient to use. How to add a Markdown editor for WordPress? I tried some plugins and find they have their strengthens and disadvantages. Here are my requirements: Compatible with my existing posts. They should still display well. I can accept minimum…
I have a Fedora Linux server with Gnome 3. I want to lock / unlock the remote Gnome desktop remotely. How to activate or deactivate it remotely through SSH? Use gnome-screensaver-command. It is not specific to Gnome 3. Turn the screensaver on (blank the screen): $ gnome-screensaver-command -a If the screensaver is active then deactivate…