1 files changed, 484 insertions, 40 deletions

diff --git a/spec/ruby/optional/capi/io_spec.rb b/spec/ruby/optional/capi/io_spec.rb
index 92bc2da54e..35bd856e00 100644
--- a/spec/ruby/optional/capi/io_spec.rb
+++ b/spec/ruby/optional/capi/io_spec.rb
@@ -1,4 +1,5 @@
-require File.expand_path('../spec_helper', __FILE__)
+require_relative 'spec_helper'
+require_relative '../../fixtures/io'
 
 load_extension('io')
 
@@ -9,12 +10,12 @@ describe "C-API IO function" do
     @name = tmp("c_api_rb_io_specs")
     touch @name
 
-    @io = new_io @name, fmode("w:utf-8")
+    @io = new_io @name, "w:utf-8"
     @io.sync = true
   end
 
   after :each do
-    @io.close unless @io.closed?
+    @io.close
     rm_r @name
   end
 
@@ -33,7 +34,7 @@ describe "C-API IO function" do
     end
 
     it "returns the io" do
-      @o.rb_io_addstr(@io, "rb_io_addstr data").should eql(@io)
+      @o.rb_io_addstr(@io, "rb_io_addstr data").should.eql?(@io)
     end
   end
 
@@ -113,19 +114,19 @@ describe "C-API IO function" do
     @name = tmp("c_api_io_specs")
     touch @name
 
-    @io = new_io @name, fmode("r:utf-8")
+    @io = new_io @name, "r:utf-8"
   end
 
   after :each do
-    @io.close unless @io.closed?
+    @io.close
     rm_r @name
   end
 
   describe "rb_io_close" do
     it "closes an IO object" do
-      @io.closed?.should be_false
+      @io.closed?.should == false
       @o.rb_io_close(@io)
-      @io.closed?.should be_true
+      @io.closed?.should == true
     end
   end
 
@@ -135,19 +136,29 @@ describe "C-API IO function" do
     end
 
     it "returns nil for non IO objects" do
-      @o.rb_io_check_io({}).should be_nil
+      @o.rb_io_check_io({}).should == nil
     end
   end
 
   describe "rb_io_check_closed" do
     it "does not raise an exception if the IO is not closed" do
       # The MRI function is void, so we use should_not raise_error
-      lambda { @o.rb_io_check_closed(@io) }.should_not raise_error
+      -> { @o.rb_io_check_closed(@io) }.should_not.raise
     end
 
     it "raises an error if the IO is closed" do
       @io.close
-      lambda { @o.rb_io_check_closed(@io) }.should raise_error(IOError)
+      -> { @o.rb_io_check_closed(@io) }.should.raise(IOError)
+    end
+  end
+
+  describe "rb_io_set_nonblock" do
+    platform_is_not :windows do
+      it "returns true when nonblock flag is set" do
+        require 'io/nonblock'
+        @o.rb_io_set_nonblock(@io)
+        @io.nonblock?.should == true
+      end
     end
   end
 
@@ -155,23 +166,28 @@ describe "C-API IO function" do
   # object is frozen, *not* if it's tainted.
   describe "rb_io_taint_check" do
     it "does not raise an exception if the IO is not frozen" do
-      lambda { @o.rb_io_taint_check(@io) }.should_not raise_error
+      -> { @o.rb_io_taint_check(@io) }.should_not.raise
     end
 
     it "raises an exception if the IO is frozen" do
       @io.freeze
 
-      lambda { @o.rb_io_taint_check(@io) }.should raise_error(RuntimeError)
+      -> { @o.rb_io_taint_check(@io) }.should.raise(RuntimeError)
     end
   end
 
-  describe "GetOpenFile" do
+  describe "rb_io_descriptor or GetOpenFile" do
     it "allows access to the system fileno" do
       @o.GetOpenFile_fd($stdin).should == 0
       @o.GetOpenFile_fd($stdout).should == 1
       @o.GetOpenFile_fd($stderr).should == 2
       @o.GetOpenFile_fd(@io).should == @io.fileno
     end
+
+    it "raises IOError if the IO is closed" do
+      @io.close
+      -> { @o.GetOpenFile_fd(@io) }.should.raise(IOError, "closed stream")
+    end
   end
 
   describe "rb_io_binmode" do
@@ -181,7 +197,7 @@ describe "C-API IO function" do
 
     it "sets binmode" do
       @o.rb_io_binmode(@io)
-      @io.binmode?.should be_true
+      @io.binmode?.should == true
     end
   end
 end
@@ -193,75 +209,127 @@ describe "C-API IO function" do
 
     @name = tmp("c_api_io_specs")
     touch @name
-    @rw_io = new_io @name, fmode("w+")
+    @rw_io = new_io @name, "w+"
   end
 
   after :each do
-    @r_io.close unless @r_io.closed?
-    @w_io.close unless @w_io.closed?
-    @rw_io.close unless @rw_io.closed?
+    @r_io.close
+    @w_io.close
+    @rw_io.close
     rm_r @name
   end
 
   describe "rb_io_check_readable" do
     it "does not raise an exception if the IO is opened for reading" do
       # The MRI function is void, so we use should_not raise_error
-      lambda { @o.rb_io_check_readable(@r_io) }.should_not raise_error
+      -> { @o.rb_io_check_readable(@r_io) }.should_not.raise
     end
 
     it "does not raise an exception if the IO is opened for read and write" do
-      lambda { @o.rb_io_check_readable(@rw_io) }.should_not raise_error
+      -> { @o.rb_io_check_readable(@rw_io) }.should_not.raise
     end
 
     it "raises an IOError if the IO is not opened for reading" do
-      lambda { @o.rb_io_check_readable(@w_io) }.should raise_error(IOError)
+      -> { @o.rb_io_check_readable(@w_io) }.should.raise(IOError)
     end
 
   end
 
   describe "rb_io_check_writable" do
-    it "does not raise an exeption if the IO is opened for writing" do
+    it "does not raise an exception if the IO is opened for writing" do
       # The MRI function is void, so we use should_not raise_error
-      lambda { @o.rb_io_check_writable(@w_io) }.should_not raise_error
+      -> { @o.rb_io_check_writable(@w_io) }.should_not.raise
     end
 
     it "does not raise an exception if the IO is opened for read and write" do
-      lambda { @o.rb_io_check_writable(@rw_io) }.should_not raise_error
+      -> { @o.rb_io_check_writable(@rw_io) }.should_not.raise
     end
 
     it "raises an IOError if the IO is not opened for reading" do
-      lambda { @o.rb_io_check_writable(@r_io) }.should raise_error(IOError)
+      -> { @o.rb_io_check_writable(@r_io) }.should.raise(IOError)
     end
   end
 
   describe "rb_io_wait_writable" do
     it "returns false if there is no error condition" do
-      @o.rb_io_wait_writable(@w_io).should be_false
+      @o.errno = 0
+      @o.rb_io_wait_writable(@w_io).should == false
+    end
+
+    it "raises an IOError if the IO is closed" do
+      @w_io.close
+      -> { @o.rb_io_wait_writable(@w_io) }.should.raise(IOError)
+    end
+  end
+
+  describe "rb_io_maybe_wait_writable" do
+    it "returns mask for events if operation was interrupted" do
+      @o.rb_io_maybe_wait_writable(Errno::EINTR::Errno, @w_io, nil).should == IO::WRITABLE
+    end
+
+    it "returns 0 if there is no error condition" do
+      @o.rb_io_maybe_wait_writable(0, @w_io, nil).should == 0
     end
 
     it "raises an IOError if the IO is closed" do
       @w_io.close
-      lambda { @o.rb_io_wait_writable(@w_io) }.should raise_error(IOError)
+      -> { @o.rb_io_maybe_wait_writable(0, @w_io, nil) }.should.raise(IOError, "closed stream")
+    end
+
+    it "raises an IOError if the IO is not initialized" do
+      -> { @o.rb_io_maybe_wait_writable(0, IO.allocate, nil) }.should.raise(IOError, "uninitialized stream")
+    end
+
+    it "can be interrupted" do
+      IOSpec.exhaust_write_buffer(@w_io)
+      start = Process.clock_gettime(Process::CLOCK_MONOTONIC)
+
+      t = Thread.new do
+        @o.rb_io_maybe_wait_writable(0, @w_io, 10)
+      end
+
+      Thread.pass until t.stop?
+      t.kill
+      t.join
+
+      finish = Process.clock_gettime(Process::CLOCK_MONOTONIC)
+      (finish - start).should < 9
     end
   end
 
   describe "rb_thread_fd_writable" do
     it "waits til an fd is ready for writing" do
-      @o.rb_thread_fd_writable(@w_io).should be_nil
+      @o.rb_thread_fd_writable(@w_io).should == nil
+    end
+  end
+
+  describe "rb_thread_fd_select" do
+    it "waits until an fd is ready for reading" do
+      @w_io.write "rb_thread_fd_select"
+      @o.rb_thread_fd_select_read(@r_io).should == 1
+    end
+
+    it "waits until an fd is ready for writing" do
+      @o.rb_thread_fd_select_write(@w_io).should == 1
+    end
+
+    it "waits until an fd is ready for writing with timeout" do
+      @o.rb_thread_fd_select_timeout(@w_io).should == 1
     end
   end
 
   platform_is_not :windows do
     describe "rb_io_wait_readable" do
       it "returns false if there is no error condition" do
-        @o.rb_io_wait_readable(@r_io, false).should be_false
+        @o.errno = 0
+        @o.rb_io_wait_readable(@r_io, false).should == false
       end
 
       it "raises and IOError if passed a closed stream" do
         @r_io.close
-        lambda {
+        -> {
           @o.rb_io_wait_readable(@r_io, false)
-        }.should raise_error(IOError)
+        }.should.raise(IOError)
       end
 
       it "blocks until the io is readable and returns true" do
@@ -271,12 +339,60 @@ describe "C-API IO function" do
           @w_io.write "rb_io_wait_readable"
         end
 
-        @o.rb_io_wait_readable(@r_io, true).should be_true
+        @o.errno = Errno::EAGAIN.new.errno
+        @o.rb_io_wait_readable(@r_io, true).should == true
         @o.instance_variable_get(:@read_data).should == "rb_io_wait_re"
 
         thr.join
       end
     end
+
+    describe "rb_io_maybe_wait_readable" do
+      it "returns mask for events if operation was interrupted" do
+        @o.rb_io_maybe_wait_readable(Errno::EINTR::Errno, @r_io, nil, false).should == IO::READABLE
+      end
+
+      it "returns 0 if there is no error condition" do
+        @o.rb_io_maybe_wait_readable(0, @r_io, nil, false).should == 0
+      end
+
+      it "blocks until the io is readable and returns events that actually occurred" do
+        @o.instance_variable_set :@write_data, false
+        thr = Thread.new do
+          Thread.pass until @o.instance_variable_get(:@write_data)
+          @w_io.write "rb_io_wait_readable"
+        end
+
+        @o.rb_io_maybe_wait_readable(Errno::EAGAIN::Errno, @r_io, IO::READABLE, true).should == IO::READABLE
+        @o.instance_variable_get(:@read_data).should == "rb_io_wait_re"
+
+        thr.join
+      end
+
+      it "can be interrupted" do
+        start = Process.clock_gettime(Process::CLOCK_MONOTONIC)
+
+        t = Thread.new do
+          @o.rb_io_maybe_wait_readable(0, @r_io, 10, false)
+        end
+
+        Thread.pass until t.stop?
+        t.kill
+        t.join
+
+        finish = Process.clock_gettime(Process::CLOCK_MONOTONIC)
+        (finish - start).should < 9
+      end
+
+      it "raises an IOError if the IO is closed" do
+        @r_io.close
+        -> { @o.rb_io_maybe_wait_readable(0, @r_io, nil, false) }.should.raise(IOError, "closed stream")
+      end
+
+      it "raises an IOError if the IO is not initialized" do
+        -> { @o.rb_io_maybe_wait_readable(0, IO.allocate, nil, false) }.should.raise(IOError, "uninitialized stream")
+      end
+    end
   end
 
   describe "rb_thread_wait_fd" do
@@ -290,35 +406,285 @@ describe "C-API IO function" do
 
       Thread.pass until start
 
-      @o.rb_thread_wait_fd(@r_io).should be_nil
+      @o.rb_thread_wait_fd(@r_io).should == nil
+
+      thr.join
+    end
+  end
+
+  describe "rb_wait_for_single_fd" do
+    it "waits til an fd is ready for reading" do
+      start = false
+      thr = Thread.new do
+        start = true
+        sleep 0.05
+        @w_io.write "rb_io_wait_readable"
+      end
+
+      Thread.pass until start
+
+      @o.rb_wait_for_single_fd(@r_io, 1, nil, nil).should == 1
 
       thr.join
     end
+
+    it "polls whether an fd is ready for reading if timeout is 0" do
+      @o.rb_wait_for_single_fd(@r_io, 1, 0, 0).should == 0
+    end
+  end
+
+  describe "rb_io_maybe_wait" do
+    it "waits til an fd is ready for reading" do
+      start = false
+      thr = Thread.new do
+        start = true
+        sleep 0.05
+        @w_io.write "rb_io_maybe_wait"
+      end
+
+      Thread.pass until start
+
+      @o.rb_io_maybe_wait(Errno::EAGAIN::Errno, @r_io, IO::READABLE, nil).should == IO::READABLE
+
+      thr.join
+    end
+
+    it "returns mask for events if operation was interrupted" do
+      @o.rb_io_maybe_wait(Errno::EINTR::Errno, @w_io, IO::WRITABLE, nil).should == IO::WRITABLE
+    end
+
+    it "raises an IOError if the IO is closed" do
+      @w_io.close
+      -> { @o.rb_io_maybe_wait(0, @w_io, IO::WRITABLE, nil) }.should.raise(IOError, "closed stream")
+    end
+
+    it "raises an IOError if the IO is not initialized" do
+      -> { @o.rb_io_maybe_wait(0, IO.allocate, IO::WRITABLE, nil) }.should.raise(IOError, "uninitialized stream")
+    end
+
+    it "can be interrupted when waiting for READABLE event" do
+      start = Process.clock_gettime(Process::CLOCK_MONOTONIC)
+
+      t = Thread.new do
+        @o.rb_io_maybe_wait(0, @r_io, IO::READABLE, 10)
+      end
+
+      Thread.pass until t.stop?
+      t.kill
+      t.join
+
+      finish = Process.clock_gettime(Process::CLOCK_MONOTONIC)
+      (finish - start).should < 9
+    end
+
+    it "can be interrupted when waiting for WRITABLE event" do
+      IOSpec.exhaust_write_buffer(@w_io)
+      start = Process.clock_gettime(Process::CLOCK_MONOTONIC)
+
+      t = Thread.new do
+        @o.rb_io_maybe_wait(0, @w_io, IO::WRITABLE, 10)
+      end
+
+      Thread.pass until t.stop?
+      t.kill
+      t.join
+
+      finish = Process.clock_gettime(Process::CLOCK_MONOTONIC)
+      (finish - start).should < 9
+    end
+  end
+
+  describe "rb_io_mode" do
+    it "returns the mode" do
+      (@o.rb_io_mode(@r_io) & 0b11).should == 0b01
+      (@o.rb_io_mode(@w_io) & 0b11).should == 0b10
+      (@o.rb_io_mode(@rw_io) & 0b11).should == 0b11
+    end
+  end
+
+  describe "rb_io_path" do
+    it "returns the IO#path" do
+      @o.rb_io_path(@r_io).should == @r_io.path
+      @o.rb_io_path(@rw_io).should == @rw_io.path
+      @o.rb_io_path(@rw_io).should == @name
+    end
+  end
+
+  describe "rb_io_closed_p" do
+    it "returns false when io is not closed" do
+      @o.rb_io_closed_p(@r_io).should == false
+      @r_io.closed?.should == false
+    end
+
+    it "returns true when io is closed" do
+      @r_io.close
+
+      @o.rb_io_closed_p(@r_io).should == true
+      @r_io.closed?.should == true
+    end
+  end
+
+  quarantine! do # "Errno::EBADF: Bad file descriptor" at closing @r_io, @rw_io etc in the after :each hook
+    describe "rb_io_open_descriptor" do
+      it "creates a new IO instance" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.should.is_a?(IO)
+      end
+
+      it "return an instance of the specified class" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.class.should == File
+
+        io = @o.rb_io_open_descriptor(IO, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.class.should == IO
+      end
+
+      it "sets the specified file descriptor" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.fileno.should == @r_io.fileno
+      end
+
+      it "sets the specified path" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.path.should == "a.txt"
+      end
+
+      it "sets the specified mode" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, CApiIOSpecs::FMODE_BINMODE, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.should.binmode?
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, CApiIOSpecs::FMODE_TEXTMODE, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.should_not.binmode?
+      end
+
+      it "sets the specified timeout" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.timeout.should == 60
+      end
+
+      it "sets the specified internal encoding" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.internal_encoding.should == Encoding::US_ASCII
+      end
+
+      it "sets the specified external encoding" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.external_encoding.should == Encoding::UTF_8
+      end
+
+      it "does not apply the specified encoding flags" do
+        name = tmp("rb_io_open_descriptor_specs")
+        File.write(name, "123\r\n456\n89")
+        file = File.open(name, "r")
+
+        io = @o.rb_io_open_descriptor(File, file.fileno, CApiIOSpecs::FMODE_READABLE, "a.txt", 60, "US-ASCII", "UTF-8", CApiIOSpecs::ECONV_UNIVERSAL_NEWLINE_DECORATOR, {})
+        io.read_nonblock(20).should == "123\r\n456\n89"
+      ensure
+        file.close
+        rm_r name
+      end
+
+      it "ignores the IO open options" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {external_encoding: "windows-1251"})
+        io.external_encoding.should == Encoding::UTF_8
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {internal_encoding: "windows-1251"})
+        io.internal_encoding.should == Encoding::US_ASCII
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {encoding: "windows-1251:binary"})
+        io.external_encoding.should == Encoding::UTF_8
+        io.internal_encoding.should == Encoding::US_ASCII
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {textmode: false})
+        io.should_not.binmode?
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {binmode: true})
+        io.should_not.binmode?
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {autoclose: false})
+        io.should.autoclose?
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {path: "a.txt"})
+        io.path.should == "a.txt"
+      end
+
+      it "ignores the IO encoding options" do
+        io = @o.rb_io_open_descriptor(File, @w_io.fileno, CApiIOSpecs::FMODE_WRITABLE, "a.txt", 60, "US-ASCII", "UTF-8", 0, {crlf_newline: true})
+
+        io.write("123\r\n456\n89")
+        io.flush
+
+        @r_io.read_nonblock(20).should == "123\r\n456\n89"
+      end
+
+      it "allows wrong mode" do
+        io = @o.rb_io_open_descriptor(File, @w_io.fileno, CApiIOSpecs::FMODE_READABLE, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.should.is_a?(File)
+
+        platform_is_not :windows do
+          -> { io.read_nonblock(1) }.should.raise(Errno::EBADF)
+        end
+
+        platform_is :windows do
+          -> { io.read_nonblock(1) }.should.raise(IO::EWOULDBLOCKWaitReadable)
+        end
+      end
+
+      it "tolerates NULL as rb_io_encoding *encoding parameter" do
+        io = @o.rb_io_open_descriptor_without_encoding(File, @r_io.fileno, 0, "a.txt", 60)
+        io.should.is_a?(File)
+      end
+
+      it "deduplicates path String" do
+        path = "a.txt".dup
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, path, 60, "US-ASCII", "UTF-8", 0, {})
+        io.path.should_not.equal?(path)
+
+        path = "a.txt".freeze
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, path, 60, "US-ASCII", "UTF-8", 0, {})
+        io.path.should_not.equal?(path)
+      end
+
+      it "calls #to_str to convert a path to a String" do
+        path = Object.new
+        def path.to_str; "a.txt"; end
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, path, 60, "US-ASCII", "UTF-8", 0, {})
+
+        io.path.should == "a.txt"
+      end
+    end
   end
 
+  ruby_version_is "3.4" do
+    describe "rb_io_maybe_wait" do
+      it "returns nil if there is no error condition" do
+        @o.rb_io_maybe_wait(0, @w_io, IO::WRITABLE, nil).should == nil
+      end
+    end
+  end
 end
 
 describe "rb_fd_fix_cloexec" do
-
   before :each do
     @o = CApiIOSpecs.new
 
     @name = tmp("c_api_rb_io_specs")
     touch @name
 
-    @io = new_io @name, fmode("w:utf-8")
+    @io = new_io @name, "w:utf-8"
     @io.close_on_exec = false
     @io.sync = true
   end
 
   after :each do
-    @io.close unless @io.closed?
+    @io.close
     rm_r @name
   end
 
   it "sets close_on_exec on the IO" do
     @o.rb_fd_fix_cloexec(@io)
-    @io.close_on_exec?.should be_true
+    @io.close_on_exec?.should == true
   end
 
 end
@@ -333,12 +699,90 @@ describe "rb_cloexec_open" do
   end
 
   after :each do
-    @io.close unless @io.nil? || @io.closed?
+    @io.close if @io
     rm_r @name
   end
 
   it "sets close_on_exec on the newly-opened IO" do
     @io = @o.rb_cloexec_open(@name, 0, 0)
-    @io.close_on_exec?.should be_true
+    @io.close_on_exec?.should == true
+  end
+end
+
+describe "rb_cloexec_dup" do
+  before :each do
+    @o = CApiIOSpecs.new
+    @name = tmp("c_api_rb_io_specs")
+    touch @name
+
+    @io = new_io @name, "r"
+    @dup = nil
+  end
+
+  after :each do
+    @dup.close if @dup
+    @io.close
+    rm_r @name
+  end
+
+  it "duplicates a file descriptor and sets close_on_exec" do
+    @dup = @o.rb_cloexec_dup(@io)
+    @dup.should.close_on_exec?
+    @dup.fileno.should_not == @io.fileno
+  end
+end
+
+describe "rb_cloexec_fcntl_dupfd" do
+  before :each do
+    @o = CApiIOSpecs.new
+    @name = tmp("c_api_rb_io_specs")
+    touch @name
+
+    @io = new_io @name, "r"
+    @dup = nil
+  end
+
+  after :each do
+    @dup.close if @dup
+    @io.close
+    rm_r @name
+  end
+
+  it "duplicates a file descriptor and sets close_on_exec" do
+    @dup = @o.rb_cloexec_fcntl_dupfd(@io, 3)
+    @dup.close_on_exec?.should == true
+    @dup.fileno.should_not == @io.fileno
+  end
+
+  it "returns a file descriptor greater than or equal to minfd" do
+    @dup = @o.rb_cloexec_fcntl_dupfd(@io, 100)
+    @dup.fileno.should >= 100
+    @dup.close_on_exec?.should == true
+  end
+end
+
+describe "rb_io_t modes flags" do
+  before :each do
+    @o = CApiIOSpecs.new
+    @name = tmp("c_api_rb_io_specs")
+    touch @name
+  end
+
+  after :each do
+    rm_r @name
+  end
+
+  it "has the sync flag set if the IO object is synced in Ruby" do
+    File.open(@name) { |io|
+      io.sync = true
+      @o.rb_io_mode_sync_flag(io).should == true
+    }
+  end
+
+  it "has the sync flag unset if the IO object is not synced in Ruby" do
+    File.open(@name) { |io|
+      io.sync = false
+      @o.rb_io_mode_sync_flag(io).should == false
+    }
   end
 end