set-uid and set-gid change the effective uid as well. It is therefore

not only required to update the cache but also to set the thread-local value.

scsh/scsh.scm

@@ -317,7 +317,8 @@
 	 (with-lock eXid-lock
 	   (lambda ()
 	     (process-set-Xid Xid)
-	     (set! *eXid-cache* (process-user-effective-Xid)))))
+	     (set! *eXid-cache* (process-user-effective-Xid))
+	     (thread-set-eXid! *eXid-cache*))))
 
        (define (with-user-effective-Xid* new-eXid thunk)
 	 (let ((changed-eXid