Index: uspace/lib/libc/generic/vfs.c
===================================================================
--- uspace/lib/libc/generic/vfs.c	(revision 72bde81acaa9c2c39b124ad814001c2046dbb66d)
+++ uspace/lib/libc/generic/vfs.c	(revision f701757241001e95d2e9f1d206c98c30138347ab)
@@ -166,5 +166,8 @@
 	async_serialize_end();
 	futex_up(&vfs_phone_futex);
-	return (ssize_t) IPC_GET_ARG1(answer);
+	if (rc == EOK)
+		return (ssize_t) IPC_GET_ARG1(answer);
+	else
+		return -1;
 }
 
@@ -196,5 +199,8 @@
 	async_serialize_end();
 	futex_up(&vfs_phone_futex);
-	return (ssize_t) IPC_GET_ARG1(answer);
+	if (rc == EOK)
+		return (ssize_t) IPC_GET_ARG1(answer);
+	else
+		return -1;
 }