From 077288bc6b6b138022d7f088c4f3db73cc2f35c7 Mon Sep 17 00:00:00 2001
From: Watson <watson1978@gmail.com>
Date: Tue, 19 Jun 2012 17:07:33 +0900
Subject: [PATCH] set sync mode to write_io which is created by IO.pipe

---
 include/ruby/io.h | 1 +
 io.c              | 9 +++++++++
 2 files changed, 10 insertions(+)

diff --git a/include/ruby/io.h b/include/ruby/io.h
index e16ff11b7..6ebd58a90 100644
--- a/include/ruby/io.h
+++ b/include/ruby/io.h
@@ -59,6 +59,7 @@ long rb_io_primitive_read(struct rb_io_t *io_struct, char *buffer, long len);
 
 int rb_io_modestr_fmode(const char *modestr);
 int rb_io_modestr_oflags(const char *modestr);
+void rb_io_synchronized(rb_io_t*);
 int rb_io_wait_readable(int fd);
 int rb_io_wait_writable(int fd);
 int rb_io_read_pending(rb_io_t *io_struct);
diff --git a/io.c b/io.c
index 164b31ff0..bebea8eee 100644
--- a/io.c
+++ b/io.c
@@ -487,6 +487,13 @@ prep_io(int fd, int mode, VALUE klass, const char *path)
     return io;
 }
 
+void
+rb_io_synchronized(rb_io_t *io_struct)
+{
+    rb_io_check_initialized(io_struct);
+    io_struct->mode |= FMODE_SYNC;
+}
+
 /*
  *  call-seq:
  *     ios.syswrite(string)   => integer
@@ -4328,6 +4335,8 @@ rb_io_s_pipe(VALUE recv, SEL sel, int argc, VALUE *argv)
 
     rd = prep_io(fd[0], FMODE_READABLE, recv, NULL);
     wr = prep_io(fd[1], FMODE_WRITABLE, recv, NULL);
+    rb_io_t *io_struct_wr = ExtractIOStruct(wr);
+    rb_io_synchronized(io_struct_wr);
 
     VALUE ret = rb_assoc_new(rd, wr);
     if (rb_block_given_p()) {