HelenOS sources

RFLAGS_NT         115 kernel/arch/amd64/src/amd64.c 	write_rflags(read_rflags() & ~(RFLAGS_IOPL | RFLAGS_NT));
RFLAGS_NT          71 kernel/arch/amd64/src/syscall.c 	    RFLAGS_IF | RFLAGS_DF | RFLAGS_NT | RFLAGS_TF);
RFLAGS_NT          57 kernel/arch/amd64/src/userspace.c 	rflags &= ~RFLAGS_NT;