This code in writer.h isn't universal about rapidjson HOT 3 CLOSED

sprintf_s() is a function provided by Visual C++ 
http://msdn.microsoft.com/en-us/library/ce3zzk1k(v=vs.80).aspx

snprintf() is a C99 standard function that VC does not provide.

What does you platform provide for the same function?

Do you have any suggestion for better compatibly?

snprintf() exist on this platform (MarmaladeSDK), but project build with non 
system librares in visual studio (VS compiler for x86; gcc for ARM/MIPS or RVCT 
for ARM) or xcode(gcc).

Simple solution is to create #define like PLATFORM_UNKNOWN with minimal 
functionality (for open source compilers like gcc). User can be set this in 
configuration header file to turn off platforms specific features like 
sprintf_s. 

Please look this example 
http://cocos2d-x.org/projects/cocos2d-x/repository/revisions/master/entry/cocos2
dx/platform/CCPlatformConfig.h - this is multiplatform game engine platform 
detection header.

This issue won't be fixed recently.
In future, I will try to abstract most functions like this, and may provide 
custom number to string converter internally to remove the dependency on 
snprintf().