Ben Chuanlong Du's Blog

And let it direct your passion with reason.

Missing Grub Menu of Windows Operating System

I came across this problem after I installed both Debian and Windows 7 system on my laptop. After searching online, I found a solution to this problem. 1. Open /etc/default/grub as root user and make sure the following line is somewhere in the file and uncommented:

    GRUB_DISABLE_OS_PROBER=false …

Map Keys in macOS

Update: As of MacOS Sierra 10.12.1, the remapping of Caps Lock to Escape can be done natively in the Keyboard System Preferences pane. Follow the steps below to remap Caps Lock to Escape (without relying on 3rd party software).

  1. Open System Preferences and click on Keyboard
  2. Click on …

Map Keys in Windows

** Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement! **

If you are a heavy Vim user and you have work on Windows, it is suggested that you Swap the Caps Lock key with the Escape key. The swaped key mapping …

Make Your Linux Server Securer

  1. Define host access rules in /etc/hosts.allow and /etc/hosts.deny. Usually I only allow login to my private server from my home and work ip. If I have to login into my private server from some other network, I login to a computer at my workplace, login into …

Advanced Use of "head" and "tail"

It is suggested that you use Python instead of Shell to manipulate text files!!

Besides passing an unsigned integer as parameter to the option -n, you can also pass a signed integer to it. When a signed integer is passed to -n, it means from/to (inclusive/exclusive similar to …