this is base on twitcurl(https://github.com/%3Ca%20href=%22/service/https://code.google.com/p/twitcurl/%22%20rel=%22nofollow%22%3Ehttp://code.google.com/p/twitcurl/%3C/a%3E)

You need to adding libcurl to Xcode’s linker settings. Targets -> Build Settings -> Linking -> Other Linker Flags add this : -L/usr/lib -lcurl -lssl -lcrypto -lz