* thread.c (rb_thread_select): preserve errno if no error

occurred.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@31412 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Tue May  3 04:27:53 2011  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* thread.c (rb_thread_select): preserve errno if no error
+	  occurred.
+
 Tue May  3 03:57:04 2011  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* include/ruby/intern.h (rb_w32_fdcopy): add prototype.  fixes

thread.c

@@ -2672,7 +2672,7 @@ rb_thread_select(int max, fd_set * read, fd_set * write, fd_set * except,
 	return 0;
     }
     else {
-	int lerrno;
+	int lerrno = errno;
 	int result;
 
 	BLOCKING_REGION({