1 files changed, 6 insertions, 2 deletions
diff --git a/ext/socket/socket.c b/ext/socket/socket.c
index 3605e991f0..37094026e4 100644
--- a/ext/socket/socket.c
+++ b/ext/socket/socket.c
@@ -373,10 +373,14 @@ s_recv(sock, argc, argv, from)
     if (flg == Qnil) flags = 0;
     else             flags = NUM2INT(flg);
 
-    str = rb_str_new(0, NUM2INT(len));
-
     GetOpenFile(sock, fptr);
+    if (rb_read_pending(fptr->f)) {
+	rb_raise(rb_eIOError, "recv for buffered IO");
+    }
     fd = fileno(fptr->f);
+
+    str = rb_str_new(0, NUM2INT(len));
+
     rb_thread_wait_fd(fd);
     TRAP_BEG;
   retry: