======**void *ioFindExternalFunctionIn(char *lookupName, void *moduleHandle)**====== **Parms**: lookupName char * to function name moduleHandle magic number that identifies the module **return**: entry address of the function, later we jump to that address hoping to execute code, or zero **From**: Interpreter **Why**: Need to load entry point of function for later use in a procedure call **Responsibility**: must return zero, or a valid address of executable code. **MacIntosh** //os-9/OSXCarbon// copy of the unix code //Cocoa:// rewritten unix code **iPhone** Not supported **Unix** invokes dlsym() returns the address of the code or data location specified by the null-terminated character string symbol. Which libraries and bundles are searched depends on the handle parameter. **Windows** Simple, GetProcAddress **BUGS**