Wow, so many wrong answers in this subthread. From the execlp manpage: "The list of arguments must be terminated by a null pointer, and, since these are variad

Wow, so many wrong answers in this subthread. From the execlp manpage: "The list of arguments must be terminated by a null pointer, and, since these are variadic functions, this pointer must be cast (char *) NULL." Using bare "NULL" or "nullptr" in this context is wrong (although you might get away with the former on many platforms).