Question

I have this code:

#include <iostream> #include <mp4.h>  int main (int argc, char * const argv[]) {     // insert code here...     std::cout << 'Hello, World!\n';      MP4Read('filename', MP4_DETAILS_ALL );      return 0; } 

And i’ve added -I/opt/local/include and -L/opt/local/lib to the path (where the mp4 library resides after installing it through macports), but all i get is:

Undefined symbols: ‘_MP4Read’, referenced from: _main in main.o ld: symbol(s) not found

Even though XCode finds it and autocompletes properly…

Answer 1

You need to link the library most likely, i.e. add -lmp4 or similar to your linking commands.