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git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@33595 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

io.c

@@ -226,7 +226,7 @@ rb_cloexec_dup2(int oldfd, int newfd)
             ret = dup3(oldfd, newfd, O_CLOEXEC);
             if (ret != -1)
                 return ret;
-            /* dup3 is available since Linux 2.6.27. */
+            /* dup3 is available since Linux 2.6.27, glibc 2.9. */
             if (errno == ENOSYS) {
                 try_dup3 = 0;
                 ret = dup2(oldfd, newfd);
@@ -261,7 +261,7 @@ rb_cloexec_pipe(int fildes[2])
         if (ret != -1)
             return ret;
 #endif
-        /* pipe2 is available since Linux 2.6.27. */
+        /* pipe2 is available since Linux 2.6.27, glibc 2.9. */
         if (errno == ENOSYS) {
             try_pipe2 = 0;
             ret = pipe(fildes);