diff --git a/libc/decl/errno_values.h b/libc/decl/errno_values.h
index e1623bef..098dfdfa 100644
--- a/libc/decl/errno_values.h
+++ b/libc/decl/errno_values.h
@@ -39,6 +39,7 @@
 #define ENODRV 47
 #define E2BIG 48
 #define EFBIG 49
+#define EXDEV 50
 
 #define EOPNOTSUPP ENOTSUP
 
diff --git a/libc/strerror.cpp b/libc/strerror.cpp
index 8e3d32f2..b8b5152e 100644
--- a/libc/strerror.cpp
+++ b/libc/strerror.cpp
@@ -68,6 +68,7 @@ extern "C" const char* sortix_strerror(int errnum)
 	case ENODRV: return "No such driver";
 	case E2BIG: return "Argument list too long";
 	case EFBIG: return "File too large";
+	case EXDEV: return "Improper link";
 	default: return "Unknown error condition";
 	}
 }