diff --git a/src/basic/fd-util.h b/src/basic/fd-util.h
index bb9669a84e..2663ff8aac 100644
--- a/src/basic/fd-util.h
+++ b/src/basic/fd-util.h
@@ -57,6 +57,13 @@
 #define NR_OPEN_MINIMUM ((unsigned) (sizeof(long) * 8))
 #define NR_OPEN_MAXIMUM ((unsigned) (CONST_MIN((size_t) INT_MAX, SIZE_MAX / __SIZEOF_POINTER__) & ~(sizeof(long) * 8 - 1)))
 
+/* A special fd that can be passed in various helpers instead of an fd indicating the root dir. Inspired by,
+ * and an alternative to AT_FDCWD. We use specific negative value that is outside of the negative errno
+ * range, to avoid any potential ambiguities. */
+#define XAT_FDROOT -8192
+assert_cc(XAT_FDROOT != AT_FDCWD);
+assert_cc(XAT_FDROOT < -ERRNO_MAX);
+
 int close_nointr(int fd);
 int safe_close(int fd);
 void safe_close_pair(int p[static 2]);