* io.c (rb_io_seek_m): Accept :CUR, :END, :SET as "whence" argument.

  (interpret_seek_whence): New function.
  [ruby-dev:45818] [Feature #6643]



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@40084 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 20 insertions, 0 deletions

diff --git a/test/ruby/test_io.rb b/test/ruby/test_io.rb
index 8ccb5de03b..b968bb6fcd 100644
--- a/test/ruby/test_io.rb
+++ b/test/ruby/test_io.rb
@@ -1514,6 +1514,26 @@ class TestIO < Test::Unit::TestCase
     }
   end
 
+  def test_seek_symwhence
+    make_tempfile {|t|
+      open(t.path) { |f|
+        f.seek(9, :SET)
+        assert_equal("az\n", f.read)
+      }
+
+      open(t.path) { |f|
+        f.seek(-4, :END)
+        assert_equal("baz\n", f.read)
+      }
+
+      open(t.path) { |f|
+        assert_equal("foo\n", f.gets)
+        f.seek(2, :CUR)
+        assert_equal("r\nbaz\n", f.read)
+      }
+    }
+  end
+
   def test_sysseek
     make_tempfile {|t|
       open(t.path) do |f|