diff --git a/libc/include/sys/linux-unistd.h b/libc/include/sys/linux-unistd.h
index ae9077f..da57f55 100644
--- a/libc/include/sys/linux-unistd.h
+++ b/libc/include/sys/linux-unistd.h
@@ -199,6 +199,7 @@
 int              delete_module (const char*, unsigned int);
 int              klogctl (int, char *, int);
 int              sysinfo (struct sysinfo *);
+int              personality (unsigned long);
 int              futex (void *, int, int, void *, void *, int);
 int              epoll_create (int size);
 int              epoll_ctl (int epfd, int op, int fd, struct epoll_event *event);