You need spaces between the string literals and the macros in the macro definition
//Note the spaces
#define NTALK_LOGFILE "logs" DIR_SYM "channels" DIR_SYM "ntalk.txt"
The same for DELETE_DIR.
By the way, I assume DIR_SYM expands to "/" or "\\" depending on whether the OS is Windows or UNIX. Windows understands forwards slashes in paths at the API level, so you don't need to do that. This: