Bash script to create a file with increment bytes
for ((x=0;x<=255;x++)); do a=`echo “obase=16; $x”|bc`;echo -n -e “\x$a”; done
一本由讀computer science嘅人所寫嘅哲學書
我而家總結一下書中所帶出的哲學問題，所有讀computer science嘅人都應該花時間思考一下: 神。人。機械人。三者之關係 機械人的超限作用 人好明顯就是當機械人係奴隸 機械人之自我認同，自我意識 克隆人是機械人? 人是機械人?
佛教中的鬼與香港人普遍認為的鬼是不同的
雜心論對鬼有比較祥細的描述：1. 鬼有六識：眼意鼻舌身意，中國人普遍認為鬼無肉身，所以無身識2. 六道中各有不同的鬼，人死變人鬼，畜牲死變畜牲鬼，最特別的就是地獄眾生死後變死獄的鬼，由此可見地獄道眾生不是鬼，而餓鬼的眾生也不是鬼，如果不是鬼又怎會死了才變鬼呢3. 鬼經過女性的陰道投胎，而不是飛入個肚到投胎4. 有兩種說法，人道的鬼只能見到人道的鬼，第二種說法是人道的鬼可以見到比人道更低層次(地獄/畜牲/餓鬼)的鬼5. 鬼有時是見不到其它的鬼的，而中國的鬼應該是一定見到其它鬼的6. 鬼入胎後近右手為男，近左手為女，中國的鬼無此說法7. 地獄道的鬼頭向下腳向上而行走，只有天道的鬼才會飛8. 六道中各道的鬼與其道眾生，身型大小相差不遠
Change github account in terminal
$git credential-osxkeychain erasehost=github.comprotocol=https[Press Return] To add your new account you can do the following commands:git config –global user.name “YOUR NAME”git config –global user.email “YOUR EMAIL ADDRESS”
Godaddy cheap VPS之經驗
係Godaddy起左隻最Cheap VPS, $160蚊個月, 得一粒vcore同1GB Ram, 行ubuntu + mysql + apache + wordpress. 正常黎講要兩三個星期restart一次mysql因為out of memory. 行wordpres兩年之後response time趑黎越慢, 有成十秒先load到個page. 裝左W3 Total Cache之後快左好多, 一兩秒就load到, 建議大家一定要裝.
Hyper-V是Type 1的Hypervisor
Hyper-V是Type 1的Hypervisor, 當你安裝完它的時侯, 它會比所在的windows更加底層, Bootloader是會首先加載它然後由它去啓動完先的那一個windows, 所以之後的vm也和那個windows同級, 所以就算那個windows死機了, 其實Hyper-V是沒有死的, 在它上面運行的vm更加不會死.
Solved: Error while finding module specification for ‘azure.cli’ (ModuleNotFoundError: No module named ‘azure’)
when you have the follow error when running azure-cli az command: /Users/peter/lib/azure-cli/bin/python: Error while finding module specification for ‘azure.cli’ (ModuleNotFoundError: No module named ‘azure’) Just run directly
I got over 2000 commits to open source projects
My github account is destroyed by a crazy Christian. I got over 2000 commits to open source projects, and 669 commits in last year. These screens are the only prove of my contribution now.
Professor Terence Parr replied
Professor Terence Parr (Antlr creator) replied, this is a major different between foreigner professor and Hong Kong professor. Professor from Hong Kong never reply any technical question from public.
Enable peter-swing theme in netbeans
Edit : /Applications/NetBeans/NetBeans 8.0.2.app/Contents/Resources/NetBeans/etc/netbeans.conf Change the line to:
objdump 2.24 has bug
objdump 2.24 has bug, but this bug is fixed in 2.25. It dump the wrong address for my 32 bits kernel.
Fixed ubuntu vnc keymap problem
ubuntu 12.04 vnc keymap has trouble, D become minimize all windows and S become start menu, run these to fix it.
disable gnome “unable to mount…” dialog
gsettings set org.gnome.desktop.media-handling automount false …and enable it again: gsettings set org.gnome.desktop.media-handling automount true
why i receive zero in my socket
I have two programs, one written in c++, the other is in java. C++ keep sending bytes to java, overtime write out 400KB. Java keep receiving the data using the readBytes function, this function returns an integer which is the number of byte it actually read for the function call. For every send (400kb) in…
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(solved) install .net 3.5 to azure windows 2012
Install the below fix will resolve this issue http://support2.microsoft.com/kb/3005628
[solved] usb wireless mouse freeze periodically in ubuntu 12.04 lts
usb wireless mouse freeze periodically in ubuntu 12.04 lts, edit /boot/grub/grub.cfg, add a boot option irqpoll will fix it
Add tabIndex to all tag incrementally
in VI, there is a command to add tabIndex to all tag incrementally :let i=200 | g/
We should mix 4K and 4M Page
I was fixing the PSE and PAE page table display for GKD, I found out Linux using 4M page to map large address space and it uses 4K page to map broken space. So advance OS should mix use of 4K and 4M page. Now GKD supports PSE=1 (4M page)
I think i am under dns attack
I think i am under dns attack, in my /var/log/message i keep seeing these. Someone is using over 2000 ip to lookup my dns server.
My new server
Just bought a 2nd hand HP server (8core + 16GB ram), cost me $2630 HKD. One 1TB 2.5″ hard disk cost me $450. Total $3080. It reboot only take 20 seconds, dell needs 5 mins (CRAZY!!!)
Analyst android ELF dependency-graph by elf-dependency-walker
Someone asked me in email about using elf-dependency-walker to analyst library or executable in linux. I found out android is using ELF format for its libraries or executables too. So the rest is simple. Please download the android emulator, within the directory there is the system image, which contain the file system. You can see in…
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solved : compile error in ffmpeg “error: invalid combination of opcode and operands”
I am using ubuntu 12.04 64 bits and trying compile ffmpeg and got this error: libavfilter/x86/vf_pullup.asm:59: error: invalid combination of opcode and operands libavfilter/x86/vf_pullup.asm:138: error: invalid combination of opcode and operands libavfilter/x86/vf_pullup.asm:175: error: invalid combination of opcode and operands To solve this, add “–disable-mmx” to your ./configure
sox and ffmpeg (convert hls into live hls) usage
These are the basic usage of SOX This script will convert ffmpeg HLS into “live streaming HLS” The above script has to run with ffmpeg: /root/download/ffmpeg-2.1.4/ffmpeg -f alsa -ac 2 -i hw:0,0 -strict experimental -acodec libmp3lame -map 0 -f segment -segment_list out.m3u8 -segment_format libmp3lame -segment_time 0.5 -segment_list_flags +live ‘a%05d.mp3’
Eclipse CDT too many semantic errors
If you have too many “semantic error” in eclipse CDT, such like this You can switch it off in project properties but unblock “Syntax and Semantic Errors”
When ESXi expire, you will see this dialog
When ESXi expire, you will see this dialog, so you know what features need money
Open vswitch overview
Start ovs monitor, look at the tabs’ name, you probably know how many function that OVS offer, this give me a big picture of integrate ova into openstack.
A very professional ppt that talk about system performance tuning
A very professional ppt that talk about system performance tuning download : scalelinuxperformance-130224171331-phpapp01
How to use QMP, send command remotely to qemu
To use qmp and send command to qemu from another process, start qemu by This will create a file /tmp/test.gmp for interchange the command. Then you can start another terminal and invoke command.txt: !!! remark, must invoke { “execute”: “qmp_capabilities” } before invoke any qmp command
PSI probe for tomcat can’t generate chart
Add this “CATALINA_OPTS=-Djava.awt.headless=true” to catalina.sh
How to change Fedora’s font rendering to get an Ubuntu-like result
Font rendering is a matter of taste. However, I personally think Ubuntu’s default font rendering is the most eye-pleasing one of the whole Linux eco-system. And if a website’s CSS font stack is looking good on Ubuntu, you can be relatively sure that it also works for Mac or MS Windows as long as the used fonts are available on these…
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