diff --git a/libc/include/sys/uio.h b/libc/include/sys/uio.h
index 0251716..187ec22 100644
--- a/libc/include/sys/uio.h
+++ b/libc/include/sys/uio.h
@@ -34,8 +34,13 @@
 
 __BEGIN_DECLS
 
-int readv(int, const struct iovec *, int);
-int writev(int, const struct iovec *, int);
+int readv(int, const struct iovec*, int);
+int writev(int, const struct iovec*, int);
+
+#if defined(__USE_GNU)
+ssize_t process_vm_readv(pid_t, const struct iovec*, unsigned long, const struct iovec*, unsigned long, unsigned long);
+ssize_t process_vm_writev(pid_t, const struct iovec*, unsigned long, const struct iovec*, unsigned long, unsigned long);
+#endif
 
 __END_DECLS