[Freeswitch-dev] quick question about the following lines of code

in file switch_loadable_module.c: switch_loadable_module_load_file(char *path, char *filename, switch_bool_t global, switch_loadable_module_t **new_module) #ifdef WIN32 dso = switch_dso_open("FreeSwitch.dll", load_global, &derr); #elif defined (MACOSX) || defined(DARWIN) dso = switch_dso_open(SWITCH_PREFIX_DIR "/lib/libfreeswitch.dylib", load_global, &derr); #else dso = switch_dso_open(NULL, load_global, &derr); #endif why the else case is dso open "NULL"? shouldn't it be lib/libfreeswitch.so?