Month: May 2014

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!!!)  


2014/05/20 0

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…
Read more


2014/05/13 0

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


2014/05/13 0

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’


2014/05/08 0

newlib’s reentrant system calls will map to non-reentrant by default

newlib’s reentrant system calls will map to non-reentrant by default. The reentrant version of open() can be found in newlib-2.1.0/newlib/libc/reent/openr.c As you can see, it will call _open which is defined in newlib-2.1.0/newlib/libgloss/libnosys/open.c . So if you don’t write your reentrant functions, it will jump to non-reentrant by default. For OS developer want to implement…
Read more


2014/05/04 0

gcc, binutils and newlib can all be compiled at once.

gcc, binutils and newlib can all be compiled at once. This article http://www.embecosm.com/appnotes/ean9/ean9-howto-newlib-1.0.pdf said gcc, binutils and newlib are from the same source tree. Using the following script can linkup all files into a single directory and compile all of them at once. Just put the directories (binutils-2.24 , gcc-4.9.0 , newlib-2.1.0) and the above script in the…
Read more


2014/05/03 1