The glibc prototype for clone uses ... and is not a direct map to the syscall args anyway. So that would not change for adding more optional args enabled by certain flags, as it did not change to add the tid pointer arguments before. But indeed the library function would have to change to pass on additional or different args to the existing syscall. Thanks, Roland -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html