diff --git a/ChangeLog b/ChangeLog
index 940fa864a2..27f838afac 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,8 +1,10 @@
-Tue Jun 22 23:59:17 2004  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+Wed Jun 23 00:00:25 2004  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* eval.c (return_jump, break_jump): raise unexpceted local jump
 	  exception directly.  [ruby-dev:23740]
 
+	* io.c (rb_io_initialize): should check fcntl result.  [ruby-dev:23742]
+
 Tue Jun 22 23:35:43 2004  NAKAMURA Usaku  <usa@ruby-lang.org>
 
 	* sprintf.c (rb_f_sprintf): support FZERO and FSPACE with NaN/Inf.
diff --git a/io.c b/io.c
index 52b4cfb05c..d26aaaf1cd 100644
--- a/io.c
+++ b/io.c
@@ -3851,6 +3851,7 @@ rb_io_initialize(argc, argv, io)
     else if (!ofp) {
 #if defined(HAVE_FCNTL) && defined(F_GETFL)
 	flags = fcntl(fd, F_GETFL);
+	if (flags == -1) rb_sys_fail(0);
 #else
 	flags = O_RDONLY;
 #endif