Cannot find openssl/crypto.h

Install openssl-devel to fix this problem.

yum install openssl-devel

How to find out Linux distribution of current machine

cat /etc/issue

How to convert a DLL to LIB for Windows

Source: http://support.microsoft.com/?scid=kb%3Ben-us%3B131313&x=1&y=15

1. Start Visual Studio Tools command promopt from Start -> Program Files -> Microsoft Visual Studio 2005 -> Visual Studio Tools -> Visual Studio 2005 Command Prompt
2. Create the .def file for the target DLL if you don't have it on hand by entering following command
  DUMPBIN /EXPORTS PATH_TO_DLL_IN_QUESTION
  (Ex. dumpbin /exports D:\Ts2Sqlite\sqlite3.dll)
3. To create the import library (.LIB), run following command
  LIB /def:PATH_TO_DEF_OF_DLL /out:OUTPUT_PATH /machine:x86
  (Ex. lib /def:D:\Ts2Sqlite\sqlite3.def /out:D:\Ts2Sqlite\sqlite3.lib /machine:x86)
4. Now you can use this LIB file along with the DLL like using a real LIB file

   

Companding or Compandsion

Companding (compression and expansion of transfer data) can be found in many different
applications, especially in digital telephone systems. A digital telephone system converts an
analog speech signal to a digital signal. This digital signal is referred to as linear—meaning
without compression. Instead of transmitting this linear digital signal across the telephone
network, this digital signal is usually first compressed before being transmitted to reduce the
transmission bandwidth. The receiver needs to expand this non-linear, compressed signal back
to a linear digital signal. Companding refers to this combined process of compression and
expansion.
Two companding format for G.711 Audio are a law and u law.

SoX raw audio data converter. wav to/from mulaw

Utility SoX (Sound Exchange)

Convert mulaw to wav:
    sox.exe -t ul input_mulaw_file output_wav_file


Convert wav to mulaw:
    sox.exe input_wav_file -r 8000 -c 1 -t ul output_mulaw_file

How to remove XCode completely

sudo /Developer/Library/uninstall-devtools –mode=all

Xcode build setting variables

For Build setting syntax, refers to http://disanji.net/iOS_Doc/#documentation/DeveloperTools/Conceptual/XcodeBuildSystem/300-Build_Settings/bs_build_settings.html

For all the build setting variables, refers to http://developer.apple.com/library/mac/#documentation/DeveloperTools/Reference/XcodeBuildSettingRef/1-Build_Setting_Reference/build_setting_ref.html

To reference a build setting value in a build setting specification, use the name of the build setting surrounded by parentheses and prefixed by the dollar-sign character ($). For example, the specification of a build setting that refers to the value of the Product Name build setting could be similar to The name of this target's product is $(PRODUCT_NAME).