diff --git a/core/file/socket_spec.rb b/core/file/socket_spec.rb
index 5d12e21f55..d3f4eb013a 100644
--- a/core/file/socket_spec.rb
+++ b/core/file/socket_spec.rb
@@ -1,42 +1,10 @@
 require_relative '../../spec_helper'
 require_relative '../../shared/file/socket'
-require 'socket'
 
 describe "File.socket?" do
   it_behaves_like :file_socket, :socket?, File
-end
 
-describe "File.socket?" do
   it "returns false if file does not exist" do
     File.socket?("I_am_a_bogus_file").should == false
   end
-
-  it "returns false if the file is not a socket" do
-    filename = tmp("i_exist")
-    touch(filename)
-
-    File.socket?(filename).should == false
-
-    rm_r filename
-  end
-end
-
-platform_is_not :windows do
-  describe "File.socket?" do
-    before :each do
-      # We need a really short name here.
-      # On Linux the path length is limited to 107, see unix(7).
-      @name = tmp("s")
-      @server = UNIXServer.new @name
-    end
-
-    after :each do
-      @server.close
-      rm_r @name
-    end
-
-    it "returns true if the file is a socket" do
-      File.socket?(@name).should == true
-    end
-  end
 end
diff --git a/core/filetest/socket_spec.rb b/core/filetest/socket_spec.rb
index 63a6a31ecb..f274be6318 100644
--- a/core/filetest/socket_spec.rb
+++ b/core/filetest/socket_spec.rb
@@ -3,4 +3,8 @@
 
 describe "FileTest.socket?" do
   it_behaves_like :file_socket, :socket?, FileTest
+
+  it "returns false if file does not exist" do
+    FileTest.socket?("I_am_a_bogus_file").should == false
+  end
 end
diff --git a/library/socket/addrinfo/afamily_spec.rb b/library/socket/addrinfo/afamily_spec.rb
index 7229dab9de..5d075be057 100644
--- a/library/socket/addrinfo/afamily_spec.rb
+++ b/library/socket/addrinfo/afamily_spec.rb
@@ -23,15 +23,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
-
-      it "returns Socket::AF_UNIX" do
-        @addrinfo.afamily.should == Socket::AF_UNIX
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
+
+    it "returns Socket::AF_UNIX" do
+      @addrinfo.afamily.should == Socket::AF_UNIX
     end
   end
 end
diff --git a/library/socket/addrinfo/family_addrinfo_spec.rb b/library/socket/addrinfo/family_addrinfo_spec.rb
index 2bc3b6a2e3..3c2f9f73d8 100644
--- a/library/socket/addrinfo/family_addrinfo_spec.rb
+++ b/library/socket/addrinfo/family_addrinfo_spec.rb
@@ -50,38 +50,36 @@
       end
     end
 
-    with_feature :unix_socket do
-      describe 'with a UNIX Addrinfo' do
-        before do
-          @source = Addrinfo.unix('cats')
-        end
+    describe 'with a UNIX Addrinfo' do
+      before do
+        @source = Addrinfo.unix('cats')
+      end
 
-        it 'raises ArgumentError if more than 1 argument is given' do
-          -> { @source.family_addrinfo('foo', 'bar') }.should raise_error(ArgumentError)
-        end
+      it 'raises ArgumentError if more than 1 argument is given' do
+        -> { @source.family_addrinfo('foo', 'bar') }.should raise_error(ArgumentError)
+      end
 
-        it 'returns an Addrinfo when a UNIX socket path is given' do
-          addr = @source.family_addrinfo('dogs')
+      it 'returns an Addrinfo when a UNIX socket path is given' do
+        addr = @source.family_addrinfo('dogs')
 
-          addr.should be_an_instance_of(Addrinfo)
-        end
+        addr.should be_an_instance_of(Addrinfo)
+      end
 
-        describe 'the returned Addrinfo' do
-          before do
-            @addr = @source.family_addrinfo('dogs')
-          end
+      describe 'the returned Addrinfo' do
+        before do
+          @addr = @source.family_addrinfo('dogs')
+        end
 
-          it 'uses AF_UNIX as the address family' do
-            @addr.afamily.should == Socket::AF_UNIX
-          end
+        it 'uses AF_UNIX as the address family' do
+          @addr.afamily.should == Socket::AF_UNIX
+        end
 
-          it 'uses PF_UNIX as the protocol family' do
-            @addr.pfamily.should == Socket::PF_UNIX
-          end
+        it 'uses PF_UNIX as the protocol family' do
+          @addr.pfamily.should == Socket::PF_UNIX
+        end
 
-          it 'uses the given socket path' do
-            @addr.unix_path.should == 'dogs'
-          end
+        it 'uses the given socket path' do
+          @addr.unix_path.should == 'dogs'
         end
       end
     end
diff --git a/library/socket/addrinfo/getnameinfo_spec.rb b/library/socket/addrinfo/getnameinfo_spec.rb
index 76579de74c..43b5a2000a 100644
--- a/library/socket/addrinfo/getnameinfo_spec.rb
+++ b/library/socket/addrinfo/getnameinfo_spec.rb
@@ -22,19 +22,17 @@
 
   platform_is :linux do
     platform_is_not :android do
-      with_feature :unix_socket do
-        describe 'using a UNIX Addrinfo' do
-          before do
-            @addr = Addrinfo.unix('cats')
-            @host = Socket.gethostname
-          end
+      describe 'using a UNIX Addrinfo' do
+        before do
+          @addr = Addrinfo.unix('cats')
+          @host = Socket.gethostname
+        end
 
-          it 'returns the hostname and UNIX socket path' do
-            host, path = @addr.getnameinfo
+        it 'returns the hostname and UNIX socket path' do
+          host, path = @addr.getnameinfo
 
-            host.should == @host
-            path.should == 'cats'
-          end
+          host.should == @host
+          path.should == 'cats'
         end
       end
     end
diff --git a/library/socket/addrinfo/initialize_spec.rb b/library/socket/addrinfo/initialize_spec.rb
index b7477efc79..bba361ef70 100644
--- a/library/socket/addrinfo/initialize_spec.rb
+++ b/library/socket/addrinfo/initialize_spec.rb
@@ -569,23 +569,21 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe 'using separate arguments for a Unix socket' do
-      before do
-        @sockaddr = Socket.pack_sockaddr_un('socket')
-      end
+  describe 'using separate arguments for a Unix socket' do
+    before do
+      @sockaddr = Socket.pack_sockaddr_un('socket')
+    end
 
-      it 'returns an Addrinfo with the correct unix path' do
-        Addrinfo.new(@sockaddr).unix_path.should == 'socket'
-      end
+    it 'returns an Addrinfo with the correct unix path' do
+      Addrinfo.new(@sockaddr).unix_path.should == 'socket'
+    end
 
-      it 'returns an Addrinfo with the correct protocol family' do
-        Addrinfo.new(@sockaddr).pfamily.should == Socket::PF_UNSPEC
-      end
+    it 'returns an Addrinfo with the correct protocol family' do
+      Addrinfo.new(@sockaddr).pfamily.should == Socket::PF_UNSPEC
+    end
 
-      it 'returns an Addrinfo with the correct address family' do
-        Addrinfo.new(@sockaddr).afamily.should == Socket::AF_UNIX
-      end
+    it 'returns an Addrinfo with the correct address family' do
+      Addrinfo.new(@sockaddr).afamily.should == Socket::AF_UNIX
     end
   end
 end
diff --git a/library/socket/addrinfo/inspect_sockaddr_spec.rb b/library/socket/addrinfo/inspect_sockaddr_spec.rb
index 70ca4dd4d7..6b18c79469 100644
--- a/library/socket/addrinfo/inspect_sockaddr_spec.rb
+++ b/library/socket/addrinfo/inspect_sockaddr_spec.rb
@@ -32,19 +32,17 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe 'using a UNIX path' do
-      it 'returns a String containing the UNIX path' do
-        addr = Addrinfo.unix('/foo/bar')
+  describe 'using a UNIX path' do
+    it 'returns a String containing the UNIX path' do
+      addr = Addrinfo.unix('/foo/bar')
 
-        addr.inspect_sockaddr.should == '/foo/bar'
-      end
+      addr.inspect_sockaddr.should == '/foo/bar'
+    end
 
-      it 'returns a String containing the UNIX path when using a relative path' do
-        addr = Addrinfo.unix('foo')
+    it 'returns a String containing the UNIX path when using a relative path' do
+      addr = Addrinfo.unix('foo')
 
-        addr.inspect_sockaddr.should == 'UNIX foo'
-      end
+      addr.inspect_sockaddr.should == 'UNIX foo'
     end
   end
 end
diff --git a/library/socket/addrinfo/inspect_spec.rb b/library/socket/addrinfo/inspect_spec.rb
index 98e1e83ffa..1442af6162 100644
--- a/library/socket/addrinfo/inspect_spec.rb
+++ b/library/socket/addrinfo/inspect_spec.rb
@@ -41,25 +41,23 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe 'using a UNIX Addrinfo' do
-      it 'returns a String' do
-        addr = Addrinfo.unix('/foo')
+  describe 'using a UNIX Addrinfo' do
+    it 'returns a String' do
+      addr = Addrinfo.unix('/foo')
 
-        addr.inspect.should == '#<Addrinfo: /foo SOCK_STREAM>'
-      end
+      addr.inspect.should == '#<Addrinfo: /foo SOCK_STREAM>'
+    end
 
-      it 'returns a String when using a relative UNIX path' do
-        addr = Addrinfo.unix('foo')
+    it 'returns a String when using a relative UNIX path' do
+      addr = Addrinfo.unix('foo')
 
-        addr.inspect.should == '#<Addrinfo: UNIX foo SOCK_STREAM>'
-      end
+      addr.inspect.should == '#<Addrinfo: UNIX foo SOCK_STREAM>'
+    end
 
-      it 'returns a String when using a DGRAM socket' do
-        addr = Addrinfo.unix('/foo', Socket::SOCK_DGRAM)
+    it 'returns a String when using a DGRAM socket' do
+      addr = Addrinfo.unix('/foo', Socket::SOCK_DGRAM)
 
-        addr.inspect.should == '#<Addrinfo: /foo SOCK_DGRAM>'
-      end
+      addr.inspect.should == '#<Addrinfo: /foo SOCK_DGRAM>'
     end
   end
 end
diff --git a/library/socket/addrinfo/ip_address_spec.rb b/library/socket/addrinfo/ip_address_spec.rb
index 4522cf5cfd..193432e861 100644
--- a/library/socket/addrinfo/ip_address_spec.rb
+++ b/library/socket/addrinfo/ip_address_spec.rb
@@ -21,15 +21,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
 
-      it "raises an exception" do
-        -> { @addrinfo.ip_address }.should raise_error(SocketError)
-      end
+    it "raises an exception" do
+      -> { @addrinfo.ip_address }.should raise_error(SocketError)
     end
   end
 
diff --git a/library/socket/addrinfo/ip_port_spec.rb b/library/socket/addrinfo/ip_port_spec.rb
index 4118607db0..f10ce35143 100644
--- a/library/socket/addrinfo/ip_port_spec.rb
+++ b/library/socket/addrinfo/ip_port_spec.rb
@@ -21,15 +21,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
 
-      it "raises an exception" do
-        -> { @addrinfo.ip_port }.should raise_error(SocketError)
-      end
+    it "raises an exception" do
+      -> { @addrinfo.ip_port }.should raise_error(SocketError)
     end
   end
 end
diff --git a/library/socket/addrinfo/ip_spec.rb b/library/socket/addrinfo/ip_spec.rb
index 80e7a62df7..09b9341605 100644
--- a/library/socket/addrinfo/ip_spec.rb
+++ b/library/socket/addrinfo/ip_spec.rb
@@ -22,15 +22,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
 
-      it "returns false" do
-        @addrinfo.ip?.should be_false
-      end
+    it "returns false" do
+      @addrinfo.ip?.should be_false
     end
   end
 end
diff --git a/library/socket/addrinfo/ip_unpack_spec.rb b/library/socket/addrinfo/ip_unpack_spec.rb
index 6c81c48d1c..58260c4557 100644
--- a/library/socket/addrinfo/ip_unpack_spec.rb
+++ b/library/socket/addrinfo/ip_unpack_spec.rb
@@ -21,15 +21,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
 
-      it "raises an exception" do
-        -> { @addrinfo.ip_unpack }.should raise_error(SocketError)
-      end
+    it "raises an exception" do
+      -> { @addrinfo.ip_unpack }.should raise_error(SocketError)
     end
   end
 end
diff --git a/library/socket/addrinfo/ipv4_loopback_spec.rb b/library/socket/addrinfo/ipv4_loopback_spec.rb
index 10ad084fc9..3a584d4f52 100644
--- a/library/socket/addrinfo/ipv4_loopback_spec.rb
+++ b/library/socket/addrinfo/ipv4_loopback_spec.rb
@@ -29,15 +29,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
 
-      it "returns false" do
-        @addrinfo.ipv4_loopback?.should be_false
-      end
+    it "returns false" do
+      @addrinfo.ipv4_loopback?.should be_false
     end
   end
 end
diff --git a/library/socket/addrinfo/ipv4_multicast_spec.rb b/library/socket/addrinfo/ipv4_multicast_spec.rb
index f7fead8640..e4b4cfcc84 100644
--- a/library/socket/addrinfo/ipv4_multicast_spec.rb
+++ b/library/socket/addrinfo/ipv4_multicast_spec.rb
@@ -15,15 +15,13 @@
     Addrinfo.ip('::1').should_not.ipv4_multicast?
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
 
-      it "returns false" do
-        @addrinfo.ipv4_multicast?.should be_false
-      end
+    it "returns false" do
+      @addrinfo.ipv4_multicast?.should be_false
     end
   end
 end
diff --git a/library/socket/addrinfo/ipv4_private_spec.rb b/library/socket/addrinfo/ipv4_private_spec.rb
index e5a33b4953..97218b5ba3 100644
--- a/library/socket/addrinfo/ipv4_private_spec.rb
+++ b/library/socket/addrinfo/ipv4_private_spec.rb
@@ -33,15 +33,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
-
-      it "returns false" do
-        @addrinfo.ipv4_private?.should be_false
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
+
+    it "returns false" do
+      @addrinfo.ipv4_private?.should be_false
     end
   end
 end
diff --git a/library/socket/addrinfo/ipv4_spec.rb b/library/socket/addrinfo/ipv4_spec.rb
index 7cba8209b6..61f7759b10 100644
--- a/library/socket/addrinfo/ipv4_spec.rb
+++ b/library/socket/addrinfo/ipv4_spec.rb
@@ -21,15 +21,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
 
-      it "returns false" do
-        @addrinfo.ipv4?.should be_false
-      end
+    it "returns false" do
+      @addrinfo.ipv4?.should be_false
     end
   end
 end
diff --git a/library/socket/addrinfo/ipv6_loopback_spec.rb b/library/socket/addrinfo/ipv6_loopback_spec.rb
index 9ff8f107bf..ffc75185ea 100644
--- a/library/socket/addrinfo/ipv6_loopback_spec.rb
+++ b/library/socket/addrinfo/ipv6_loopback_spec.rb
@@ -31,15 +31,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
-
-      it "returns false" do
-        @addrinfo.ipv6_loopback?.should be_false
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
+
+    it "returns false" do
+      @addrinfo.ipv6_loopback?.should be_false
     end
   end
 end
diff --git a/library/socket/addrinfo/ipv6_multicast_spec.rb b/library/socket/addrinfo/ipv6_multicast_spec.rb
index 2c987b5921..99d4e8cf4d 100644
--- a/library/socket/addrinfo/ipv6_multicast_spec.rb
+++ b/library/socket/addrinfo/ipv6_multicast_spec.rb
@@ -34,15 +34,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
-
-      it "returns false" do
-        @addrinfo.ipv6_multicast?.should be_false
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
+
+    it "returns false" do
+      @addrinfo.ipv6_multicast?.should be_false
     end
   end
 end
diff --git a/library/socket/addrinfo/ipv6_spec.rb b/library/socket/addrinfo/ipv6_spec.rb
index 131e38849c..436d5e930b 100644
--- a/library/socket/addrinfo/ipv6_spec.rb
+++ b/library/socket/addrinfo/ipv6_spec.rb
@@ -21,15 +21,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
 
-      it "returns false" do
-        @addrinfo.ipv6?.should be_false
-      end
+    it "returns false" do
+      @addrinfo.ipv6?.should be_false
     end
   end
 end
diff --git a/library/socket/addrinfo/ipv6_to_ipv4_spec.rb b/library/socket/addrinfo/ipv6_to_ipv4_spec.rb
index 6dfaf531ae..29050bec20 100644
--- a/library/socket/addrinfo/ipv6_to_ipv4_spec.rb
+++ b/library/socket/addrinfo/ipv6_to_ipv4_spec.rb
@@ -62,7 +62,7 @@
       Addrinfo.ip('192.168.1.1').ipv6_to_ipv4.should be_nil
     end
 
-    with_feature :unix_socket do
+    describe 'for a unix socket' do
       it 'returns nil for a UNIX Addrinfo' do
         Addrinfo.unix('foo').ipv6_to_ipv4.should be_nil
       end
diff --git a/library/socket/addrinfo/marshal_dump_spec.rb b/library/socket/addrinfo/marshal_dump_spec.rb
index 2d69a33b53..e2c3497f7f 100644
--- a/library/socket/addrinfo/marshal_dump_spec.rb
+++ b/library/socket/addrinfo/marshal_dump_spec.rb
@@ -42,40 +42,38 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe 'using a UNIX Addrinfo' do
+  describe 'using a UNIX Addrinfo' do
+    before do
+      @addr = Addrinfo.unix('foo')
+    end
+
+    it 'returns an Array' do
+      @addr.marshal_dump.should be_an_instance_of(Array)
+    end
+
+    describe 'the returned Array' do
       before do
-        @addr = Addrinfo.unix('foo')
+        @array = @addr.marshal_dump
       end
 
-      it 'returns an Array' do
-        @addr.marshal_dump.should be_an_instance_of(Array)
+      it 'includes the address family as the 1st value' do
+        @array[0].should == 'AF_UNIX'
       end
 
-      describe 'the returned Array' do
-        before do
-          @array = @addr.marshal_dump
-        end
-
-        it 'includes the address family as the 1st value' do
-          @array[0].should == 'AF_UNIX'
-        end
-
-        it 'includes the UNIX path as the 2nd value' do
-          @array[1].should == @addr.unix_path
-        end
+      it 'includes the UNIX path as the 2nd value' do
+        @array[1].should == @addr.unix_path
+      end
 
-        it 'includes the protocol family as the 3rd value' do
-          @array[2].should == 'PF_UNIX'
-        end
+      it 'includes the protocol family as the 3rd value' do
+        @array[2].should == 'PF_UNIX'
+      end
 
-        it 'includes the socket type as the 4th value' do
-          @array[3].should == 'SOCK_STREAM'
-        end
+      it 'includes the socket type as the 4th value' do
+        @array[3].should == 'SOCK_STREAM'
+      end
 
-        it 'includes the protocol as the 5th value' do
-          @array[4].should == 0
-        end
+      it 'includes the protocol as the 5th value' do
+        @array[4].should == 0
       end
     end
   end
diff --git a/library/socket/addrinfo/marshal_load_spec.rb b/library/socket/addrinfo/marshal_load_spec.rb
index aa20865224..02cef90115 100644
--- a/library/socket/addrinfo/marshal_load_spec.rb
+++ b/library/socket/addrinfo/marshal_load_spec.rb
@@ -18,18 +18,16 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe 'using a UNIX socket' do
-      it 'returns a new Addrinfo' do
-        source = Addrinfo.unix('foo')
-        addr   = Marshal.load(Marshal.dump(source))
+  describe 'using a UNIX socket' do
+    it 'returns a new Addrinfo' do
+      source = Addrinfo.unix('foo')
+      addr   = Marshal.load(Marshal.dump(source))
 
-        addr.afamily.should   == source.afamily
-        addr.pfamily.should   == source.pfamily
-        addr.socktype.should  == source.socktype
-        addr.protocol.should  == source.protocol
-        addr.unix_path.should == source.unix_path
-      end
+      addr.afamily.should   == source.afamily
+      addr.pfamily.should   == source.pfamily
+      addr.socktype.should  == source.socktype
+      addr.protocol.should  == source.protocol
+      addr.unix_path.should == source.unix_path
     end
   end
 end
diff --git a/library/socket/addrinfo/pfamily_spec.rb b/library/socket/addrinfo/pfamily_spec.rb
index 984744a964..da530b7fdc 100644
--- a/library/socket/addrinfo/pfamily_spec.rb
+++ b/library/socket/addrinfo/pfamily_spec.rb
@@ -29,15 +29,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
-
-      it "returns Socket::PF_UNIX" do
-        @addrinfo.pfamily.should == Socket::PF_UNIX
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
+
+    it "returns Socket::PF_UNIX" do
+      @addrinfo.pfamily.should == Socket::PF_UNIX
     end
   end
 end
diff --git a/library/socket/addrinfo/protocol_spec.rb b/library/socket/addrinfo/protocol_spec.rb
index ea143fc4a8..f6ffc9acf9 100644
--- a/library/socket/addrinfo/protocol_spec.rb
+++ b/library/socket/addrinfo/protocol_spec.rb
@@ -10,15 +10,13 @@
     Addrinfo.tcp('::1', 80).protocol.should == Socket::IPPROTO_TCP
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
 
-      it "returns 0" do
-        @addrinfo.protocol.should == 0
-      end
+    it "returns 0" do
+      @addrinfo.protocol.should == 0
     end
   end
 end
diff --git a/library/socket/addrinfo/shared/to_sockaddr.rb b/library/socket/addrinfo/shared/to_sockaddr.rb
index 4f7cf439a0..70d6bfbbfe 100644
--- a/library/socket/addrinfo/shared/to_sockaddr.rb
+++ b/library/socket/addrinfo/shared/to_sockaddr.rb
@@ -19,15 +19,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
-
-      it "returns a sockaddr packed structure" do
-        @addrinfo.send(@method).should == Socket.sockaddr_un('/tmp/sock')
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
+
+    it "returns a sockaddr packed structure" do
+      @addrinfo.send(@method).should == Socket.sockaddr_un('/tmp/sock')
     end
   end
 
diff --git a/library/socket/addrinfo/socktype_spec.rb b/library/socket/addrinfo/socktype_spec.rb
index b994bea140..e5f02cd759 100644
--- a/library/socket/addrinfo/socktype_spec.rb
+++ b/library/socket/addrinfo/socktype_spec.rb
@@ -9,15 +9,13 @@
     Addrinfo.tcp('127.0.0.1', 80).socktype.should == Socket::SOCK_STREAM
   end
 
-  with_feature :unix_socket do
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
 
-      it "returns Socket::SOCK_STREAM" do
-        @addrinfo.socktype.should == Socket::SOCK_STREAM
-      end
+    it "returns Socket::SOCK_STREAM" do
+      @addrinfo.socktype.should == Socket::SOCK_STREAM
     end
   end
 end
diff --git a/library/socket/addrinfo/unix_path_spec.rb b/library/socket/addrinfo/unix_path_spec.rb
index 6bfb56a4ac..2a9076a354 100644
--- a/library/socket/addrinfo/unix_path_spec.rb
+++ b/library/socket/addrinfo/unix_path_spec.rb
@@ -1,37 +1,35 @@
 require_relative '../spec_helper'
 
-with_feature :unix_socket do
-  describe "Addrinfo#unix_path" do
-    describe "for an ipv4 socket" do
+describe "Addrinfo#unix_path" do
+  describe "for an ipv4 socket" do
 
-      before :each do
-        @addrinfo = Addrinfo.tcp("127.0.0.1", 80)
-      end
-
-      it "raises an exception" do
-        -> { @addrinfo.unix_path }.should raise_error(SocketError)
-      end
+    before :each do
+      @addrinfo = Addrinfo.tcp("127.0.0.1", 80)
+    end
 
+    it "raises an exception" do
+      -> { @addrinfo.unix_path }.should raise_error(SocketError)
     end
 
-    describe "for an ipv6 socket" do
-      before :each do
-        @addrinfo = Addrinfo.tcp("::1", 80)
-      end
+  end
 
-      it "raises an exception" do
-        -> { @addrinfo.unix_path }.should raise_error(SocketError)
-      end
+  describe "for an ipv6 socket" do
+    before :each do
+      @addrinfo = Addrinfo.tcp("::1", 80)
     end
 
-    describe "for a unix socket" do
-      before :each do
-        @addrinfo = Addrinfo.unix("/tmp/sock")
-      end
+    it "raises an exception" do
+      -> { @addrinfo.unix_path }.should raise_error(SocketError)
+    end
+  end
+
+  describe "for a unix socket" do
+    before :each do
+      @addrinfo = Addrinfo.unix("/tmp/sock")
+    end
 
-      it "returns the socket path" do
-        @addrinfo.unix_path.should == "/tmp/sock"
-      end
+    it "returns the socket path" do
+      @addrinfo.unix_path.should == "/tmp/sock"
     end
   end
 end
diff --git a/library/socket/addrinfo/unix_spec.rb b/library/socket/addrinfo/unix_spec.rb
index 4596ece17e..7597533a76 100644
--- a/library/socket/addrinfo/unix_spec.rb
+++ b/library/socket/addrinfo/unix_spec.rb
@@ -1,36 +1,34 @@
 require_relative '../spec_helper'
 
-with_feature :unix_socket do
-  describe 'Addrinfo.unix' do
-    it 'returns an Addrinfo instance' do
-      Addrinfo.unix('socket').should be_an_instance_of(Addrinfo)
-    end
+describe 'Addrinfo.unix' do
+  it 'returns an Addrinfo instance' do
+    Addrinfo.unix('socket').should be_an_instance_of(Addrinfo)
+  end
 
-    it 'sets the IP address' do
-      Addrinfo.unix('socket').unix_path.should == 'socket'
-    end
+  it 'sets the IP address' do
+    Addrinfo.unix('socket').unix_path.should == 'socket'
+  end
 
-    it 'sets the address family' do
-      Addrinfo.unix('socket').afamily.should == Socket::AF_UNIX
-    end
+  it 'sets the address family' do
+    Addrinfo.unix('socket').afamily.should == Socket::AF_UNIX
+  end
 
-    it 'sets the protocol family' do
-      Addrinfo.unix('socket').pfamily.should == Socket::PF_UNIX
-    end
+  it 'sets the protocol family' do
+    Addrinfo.unix('socket').pfamily.should == Socket::PF_UNIX
+  end
 
-    it 'sets the socket type' do
-      Addrinfo.unix('socket').socktype.should == Socket::SOCK_STREAM
-    end
+  it 'sets the socket type' do
+    Addrinfo.unix('socket').socktype.should == Socket::SOCK_STREAM
+  end
 
-    it 'sets a custom socket type' do
-      addr = Addrinfo.unix('socket', Socket::SOCK_DGRAM)
+  it 'sets a custom socket type' do
+    addr = Addrinfo.unix('socket', Socket::SOCK_DGRAM)
 
-      addr.socktype.should == Socket::SOCK_DGRAM
-    end
+    addr.socktype.should == Socket::SOCK_DGRAM
+  end
 
-    it 'sets the socket protocol to 0' do
-      Addrinfo.unix('socket').protocol.should == 0
-    end
+  it 'sets the socket protocol to 0' do
+    Addrinfo.unix('socket').protocol.should == 0
   end
 end
 
diff --git a/library/socket/basicsocket/connect_address_spec.rb b/library/socket/basicsocket/connect_address_spec.rb
index 1a1c9982d9..2e318fcb85 100644
--- a/library/socket/basicsocket/connect_address_spec.rb
+++ b/library/socket/basicsocket/connect_address_spec.rb
@@ -94,61 +94,59 @@
     end
   end
 
-  with_feature :unix_socket do
-    platform_is_not :aix do
-      describe 'using an unbound UNIX socket' do
-        before do
-          @path = SocketSpecs.socket_path
-          @server = UNIXServer.new(@path)
-          @client = UNIXSocket.new(@path)
-        end
-
-        after do
-          @client.close
-          @server.close
-          rm_r(@path)
-        end
-
-        it 'raises SocketError' do
-          -> { @client.connect_address }.should raise_error(SocketError)
-        end
-      end
-    end
-
-    describe 'using a bound UNIX socket' do
+  platform_is_not :aix do
+    describe 'using an unbound UNIX socket' do
       before do
         @path = SocketSpecs.socket_path
-        @sock = UNIXServer.new(@path)
+        @server = UNIXServer.new(@path)
+        @client = UNIXSocket.new(@path)
       end
 
       after do
-        @sock.close
+        @client.close
+        @server.close
         rm_r(@path)
       end
 
-      it 'returns an Addrinfo' do
-        @sock.connect_address.should be_an_instance_of(Addrinfo)
+      it 'raises SocketError' do
+        -> { @client.connect_address }.should raise_error(SocketError)
       end
+    end
+  end
 
-      it 'uses the correct socket path' do
-        @sock.connect_address.unix_path.should == @path
-      end
+  describe 'using a bound UNIX socket' do
+    before do
+      @path = SocketSpecs.socket_path
+      @sock = UNIXServer.new(@path)
+    end
 
-      it 'uses AF_UNIX as the address family' do
-        @sock.connect_address.afamily.should == Socket::AF_UNIX
-      end
+    after do
+      @sock.close
+      rm_r(@path)
+    end
 
-      it 'uses PF_UNIX as the protocol family' do
-        @sock.connect_address.pfamily.should == Socket::PF_UNIX
-      end
+    it 'returns an Addrinfo' do
+      @sock.connect_address.should be_an_instance_of(Addrinfo)
+    end
 
-      it 'uses SOCK_STREAM as the socket type' do
-        @sock.connect_address.socktype.should == Socket::SOCK_STREAM
-      end
+    it 'uses the correct socket path' do
+      @sock.connect_address.unix_path.should == @path
+    end
 
-      it 'uses 0 as the protocol' do
-        @sock.connect_address.protocol.should == 0
-      end
+    it 'uses AF_UNIX as the address family' do
+      @sock.connect_address.afamily.should == Socket::AF_UNIX
+    end
+
+    it 'uses PF_UNIX as the protocol family' do
+      @sock.connect_address.pfamily.should == Socket::PF_UNIX
+    end
+
+    it 'uses SOCK_STREAM as the socket type' do
+      @sock.connect_address.socktype.should == Socket::SOCK_STREAM
+    end
+
+    it 'uses 0 as the protocol' do
+      @sock.connect_address.protocol.should == 0
     end
   end
 end
diff --git a/library/socket/basicsocket/getpeereid_spec.rb b/library/socket/basicsocket/getpeereid_spec.rb
index 6179211d96..2e03cd3684 100644
--- a/library/socket/basicsocket/getpeereid_spec.rb
+++ b/library/socket/basicsocket/getpeereid_spec.rb
@@ -2,7 +2,7 @@
 require_relative '../fixtures/classes'
 
 describe 'BasicSocket#getpeereid' do
-  with_feature :unix_socket do
+  platform_is_not :windows do
     describe 'using a UNIXSocket' do
       before do
         @path = SocketSpecs.socket_path
diff --git a/library/socket/basicsocket/setsockopt_spec.rb b/library/socket/basicsocket/setsockopt_spec.rb
index 1e8d84e1c9..f686e67326 100644
--- a/library/socket/basicsocket/setsockopt_spec.rb
+++ b/library/socket/basicsocket/setsockopt_spec.rb
@@ -315,22 +315,20 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe 'using a UNIX socket' do
-      before do
-        @path = SocketSpecs.socket_path
-        @server = UNIXServer.new(@path)
-      end
+  describe 'using a UNIX socket' do
+    before do
+      @path = SocketSpecs.socket_path
+      @server = UNIXServer.new(@path)
+    end
 
-      after do
-        @server.close
-        rm_r @path
-      end
+    after do
+      @server.close
+      rm_r @path
+    end
 
-      it 'sets a boolean option' do
-        @server.setsockopt(:SOCKET, :REUSEADDR, true)
-        @server.getsockopt(:SOCKET, :REUSEADDR).bool.should == true
-      end
+    it 'sets a boolean option' do
+      @server.setsockopt(:SOCKET, :REUSEADDR, true)
+      @server.getsockopt(:SOCKET, :REUSEADDR).bool.should == true
     end
   end
 end
diff --git a/library/socket/shared/address.rb b/library/socket/shared/address.rb
index f3be9cfb99..3857a40ce8 100644
--- a/library/socket/shared/address.rb
+++ b/library/socket/shared/address.rb
@@ -129,41 +129,51 @@
     end
   end
 
-  with_feature :unix_socket do
-    describe 'using UNIXSocket' do
-      before :each do
-        @path = SocketSpecs.socket_path
-        @s = UNIXServer.new(@path)
-        @a = UNIXSocket.new(@path)
-        @b = @s.accept
-        @addr = @object.call(@a)
-      end
+  describe 'using UNIXSocket' do
+    before :each do
+      @path = SocketSpecs.socket_path
+      @s = UNIXServer.new(@path)
+      @a = UNIXSocket.new(@path)
+      @b = @s.accept
+      @addr = @object.call(@a)
+    end
 
-      after :each do
-        [@b, @a, @s].each(&:close)
-        rm_r(@path)
-      end
+    after :each do
+      [@b, @a, @s].each(&:close)
+      rm_r(@path)
+    end
 
-      it 'uses AF_UNIX as the address family' do
-        @addr.afamily.should == Socket::AF_UNIX
-      end
+    it 'uses AF_UNIX as the address family' do
+      @addr.afamily.should == Socket::AF_UNIX
+    end
 
-      it 'uses PF_UNIX as the protocol family' do
-        @addr.pfamily.should == Socket::PF_UNIX
-      end
+    it 'uses PF_UNIX as the protocol family' do
+      @addr.pfamily.should == Socket::PF_UNIX
+    end
 
-      it 'uses SOCK_STREAM as the socket type' do
-        @addr.socktype.should == Socket::SOCK_STREAM
+    it 'uses SOCK_STREAM as the socket type' do
+      @addr.socktype.should == Socket::SOCK_STREAM
+    end
+
+    it 'uses the correct socket path' do
+      if @method == :local_address
+        @addr.unix_path.should == ""
+      else
+        @addr.unix_path.should == @path
       end
+    end
 
-      it 'uses the correct socket path' do
+    platform_is_not :windows do
+      it 'equals address of peer socket' do
         if @method == :local_address
-          @addr.unix_path.should == ""
+          @addr.to_s.should == @b.remote_address.to_s
         else
-          @addr.unix_path.should == @path
+          @addr.to_s.should == @b.local_address.to_s
         end
       end
+    end
 
+    guard -> { platform_is :windows and ruby_bug "#21702", ""..."4.0" } do
       it 'equals address of peer socket' do
         if @method == :local_address
           @addr.to_s.should == @b.remote_address.to_s
@@ -171,23 +181,23 @@
           @addr.to_s.should == @b.local_address.to_s
         end
       end
+    end
 
-      it 'returns an Addrinfo' do
-        @addr.should be_an_instance_of(Addrinfo)
-      end
+    it 'returns an Addrinfo' do
+      @addr.should be_an_instance_of(Addrinfo)
+    end
 
-      it 'uses 0 as the protocol' do
-        @addr.protocol.should == 0
-      end
+    it 'uses 0 as the protocol' do
+      @addr.protocol.should == 0
+    end
 
-      it 'can be used to connect to the server' do
-        skip if @method == :local_address
-        b = @addr.connect
-        begin
-          b.remote_address.to_s.should == @addr.to_s
-        ensure
-          b.close
-        end
+    it 'can be used to connect to the server' do
+      skip if @method == :local_address
+      b = @addr.connect
+      begin
+        b.remote_address.to_s.should == @addr.to_s
+      ensure
+        b.close
       end
     end
   end
diff --git a/library/socket/shared/pack_sockaddr.rb b/library/socket/shared/pack_sockaddr.rb
index f309aa02c7..4bfcf4edb9 100644
--- a/library/socket/shared/pack_sockaddr.rb
+++ b/library/socket/shared/pack_sockaddr.rb
@@ -47,23 +47,21 @@
 end
 
 describe :socket_pack_sockaddr_un, shared: true do
-  with_feature :unix_socket do
-    it 'should be idempotent' do
-      bytes = Socket.public_send(@method, '/tmp/foo').bytes
-      bytes[2..9].should == [47, 116, 109, 112, 47, 102, 111, 111]
-      bytes[10..-1].all?(&:zero?).should == true
-    end
+  it 'should be idempotent' do
+    bytes = Socket.public_send(@method, '/tmp/foo').bytes
+    bytes[2..9].should == [47, 116, 109, 112, 47, 102, 111, 111]
+    bytes[10..-1].all?(&:zero?).should == true
+  end
 
-    it "packs and unpacks" do
-      sockaddr_un = Socket.public_send(@method, '/tmp/s')
-      Socket.unpack_sockaddr_un(sockaddr_un).should == '/tmp/s'
-    end
+  it "packs and unpacks" do
+    sockaddr_un = Socket.public_send(@method, '/tmp/s')
+    Socket.unpack_sockaddr_un(sockaddr_un).should == '/tmp/s'
+  end
 
-    it "handles correctly paths with multibyte chars" do
-      sockaddr_un = Socket.public_send(@method, '/home/вася/sock')
-      path = Socket.unpack_sockaddr_un(sockaddr_un).encode('UTF-8', 'UTF-8')
-      path.should == '/home/вася/sock'
-    end
+  it "handles correctly paths with multibyte chars" do
+    sockaddr_un = Socket.public_send(@method, '/home/вася/sock')
+    path = Socket.unpack_sockaddr_un(sockaddr_un).encode('UTF-8', 'UTF-8')
+    path.should == '/home/вася/sock'
   end
 
   platform_is :linux do
@@ -84,7 +82,7 @@
     end
   end
 
-  platform_is_not :windows, :aix do
+  platform_is_not :aix do
     it "raises ArgumentError for paths that are too long" do
       # AIX doesn't raise error
       long_path = 'a' * 110
diff --git a/library/socket/socket/unix_server_loop_spec.rb b/library/socket/socket/unix_server_loop_spec.rb
index 0f34d4a50b..6192bc8bf6 100644
--- a/library/socket/socket/unix_server_loop_spec.rb
+++ b/library/socket/socket/unix_server_loop_spec.rb
@@ -1,58 +1,56 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe 'Socket.unix_server_loop' do
-    before do
-      @path = SocketSpecs.socket_path
-    end
+describe 'Socket.unix_server_loop' do
+  before do
+    @path = SocketSpecs.socket_path
+  end
 
-    after do
-      rm_r(@path) if File.file?(@path)
-    end
+  after do
+    rm_r(@path) if File.file?(@path)
+  end
 
-    describe 'when no connections are available' do
-      it 'blocks the caller' do
-        -> { Socket.unix_server_loop(@path) }.should block_caller
-      end
+  describe 'when no connections are available' do
+    it 'blocks the caller' do
+      -> { Socket.unix_server_loop(@path) }.should block_caller
     end
+  end
 
-    describe 'when a connection is available' do
-      before do
-        @client = nil
-      end
+  describe 'when a connection is available' do
+    before do
+      @client = nil
+    end
 
-      after do
-        @sock.close if @sock
-        @client.close if @client
-      end
+    after do
+      @sock.close if @sock
+      @client.close if @client
+    end
 
-      it 'yields a Socket and an Addrinfo' do
-        @sock, addr = nil
+    it 'yields a Socket and an Addrinfo' do
+      @sock, addr = nil
 
-        thread = Thread.new do
-          Socket.unix_server_loop(@path) do |socket, addrinfo|
-            @sock = socket
-            addr = addrinfo
+      thread = Thread.new do
+        Socket.unix_server_loop(@path) do |socket, addrinfo|
+          @sock = socket
+          addr = addrinfo
 
-            break
-          end
+          break
         end
+      end
 
-        SocketSpecs.loop_with_timeout do
-          begin
-            @client = Socket.unix(@path)
-          rescue SystemCallError
-            sleep 0.01
-            :retry
-          end
+      SocketSpecs.loop_with_timeout do
+        begin
+          @client = Socket.unix(@path)
+        rescue SystemCallError
+          sleep 0.01
+          :retry
         end
+      end
 
-        thread.join
+      thread.join
 
-        @sock.should be_an_instance_of(Socket)
-        addr.should be_an_instance_of(Addrinfo)
-      end
+      @sock.should be_an_instance_of(Socket)
+      addr.should be_an_instance_of(Addrinfo)
     end
   end
 end
diff --git a/library/socket/socket/unix_server_socket_spec.rb b/library/socket/socket/unix_server_socket_spec.rb
index fc357740fa..34c3b96d07 100644
--- a/library/socket/socket/unix_server_socket_spec.rb
+++ b/library/socket/socket/unix_server_socket_spec.rb
@@ -1,48 +1,46 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe 'Socket.unix_server_socket' do
+describe 'Socket.unix_server_socket' do
+  before do
+    @path = SocketSpecs.socket_path
+  end
+
+  after do
+    rm_r(@path)
+  end
+
+  describe 'when no block is given' do
     before do
-      @path = SocketSpecs.socket_path
+      @socket = nil
     end
 
     after do
-      rm_r(@path)
+      @socket.close
     end
 
-    describe 'when no block is given' do
-      before do
-        @socket = nil
-      end
-
-      after do
-        @socket.close
-      end
+    it 'returns a Socket' do
+      @socket = Socket.unix_server_socket(@path)
 
-      it 'returns a Socket' do
-        @socket = Socket.unix_server_socket(@path)
-
-        @socket.should be_an_instance_of(Socket)
-      end
+      @socket.should be_an_instance_of(Socket)
     end
+  end
 
-    describe 'when a block is given' do
-      it 'yields a Socket' do
-        Socket.unix_server_socket(@path) do |sock|
-          sock.should be_an_instance_of(Socket)
-        end
+  describe 'when a block is given' do
+    it 'yields a Socket' do
+      Socket.unix_server_socket(@path) do |sock|
+        sock.should be_an_instance_of(Socket)
       end
+    end
 
-      it 'closes the Socket when the block returns' do
-        socket = nil
-
-        Socket.unix_server_socket(@path) do |sock|
-          socket = sock
-        end
+    it 'closes the Socket when the block returns' do
+      socket = nil
 
-        socket.should be_an_instance_of(Socket)
+      Socket.unix_server_socket(@path) do |sock|
+        socket = sock
       end
+
+      socket.should be_an_instance_of(Socket)
     end
   end
 end
diff --git a/library/socket/socket/unix_spec.rb b/library/socket/socket/unix_spec.rb
index 4bff59bd4b..2a5d77f96f 100644
--- a/library/socket/socket/unix_spec.rb
+++ b/library/socket/socket/unix_spec.rb
@@ -1,45 +1,43 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe 'Socket.unix' do
-    before do
-      @path   = SocketSpecs.socket_path
-      @server = UNIXServer.new(@path)
-      @socket = nil
-    end
+describe 'Socket.unix' do
+  before do
+    @path   = SocketSpecs.socket_path
+    @server = UNIXServer.new(@path)
+    @socket = nil
+  end
 
-    after do
-      @server.close
-      @socket.close if @socket
+  after do
+    @server.close
+    @socket.close if @socket
 
-      rm_r(@path)
-    end
+    rm_r(@path)
+  end
 
-    describe 'when no block is given' do
-      it 'returns a Socket' do
-        @socket = Socket.unix(@path)
+  describe 'when no block is given' do
+    it 'returns a Socket' do
+      @socket = Socket.unix(@path)
 
-        @socket.should be_an_instance_of(Socket)
-      end
+      @socket.should be_an_instance_of(Socket)
     end
+  end
 
-    describe 'when a block is given' do
-      it 'yields a Socket' do
-        Socket.unix(@path) do |sock|
-          sock.should be_an_instance_of(Socket)
-        end
+  describe 'when a block is given' do
+    it 'yields a Socket' do
+      Socket.unix(@path) do |sock|
+        sock.should be_an_instance_of(Socket)
       end
+    end
 
-      it 'closes the Socket when the block returns' do
-        socket = nil
-
-        Socket.unix(@path) do |sock|
-          socket = sock
-        end
+    it 'closes the Socket when the block returns' do
+      socket = nil
 
-        socket.should.closed?
+      Socket.unix(@path) do |sock|
+        socket = sock
       end
+
+      socket.should.closed?
     end
   end
 end
diff --git a/library/socket/socket/unpack_sockaddr_in_spec.rb b/library/socket/socket/unpack_sockaddr_in_spec.rb
index 79ec68cd18..935b5cb543 100644
--- a/library/socket/socket/unpack_sockaddr_in_spec.rb
+++ b/library/socket/socket/unpack_sockaddr_in_spec.rb
@@ -32,15 +32,13 @@
     end
   end
 
-  with_feature :unix_socket do
-    it "raises an ArgumentError when the sin_family is not AF_INET" do
-      sockaddr = Socket.sockaddr_un '/tmp/x'
-      -> { Socket.unpack_sockaddr_in sockaddr }.should raise_error(ArgumentError)
-    end
+  it "raises an ArgumentError when the sin_family is not AF_INET" do
+    sockaddr = Socket.sockaddr_un '/tmp/x'
+    -> { Socket.unpack_sockaddr_in sockaddr }.should raise_error(ArgumentError)
+  end
 
-    it "raises an ArgumentError when passed addrinfo is not AF_INET/AF_INET6" do
-      addrinfo = Addrinfo.unix('/tmp/sock')
-      -> { Socket.unpack_sockaddr_in(addrinfo) }.should raise_error(ArgumentError)
-    end
+  it "raises an ArgumentError when passed addrinfo is not AF_INET/AF_INET6" do
+    addrinfo = Addrinfo.unix('/tmp/sock')
+    -> { Socket.unpack_sockaddr_in(addrinfo) }.should raise_error(ArgumentError)
   end
 end
diff --git a/library/socket/socket/unpack_sockaddr_un_spec.rb b/library/socket/socket/unpack_sockaddr_un_spec.rb
index 12f970f89b..6e0f11de3d 100644
--- a/library/socket/socket/unpack_sockaddr_un_spec.rb
+++ b/library/socket/socket/unpack_sockaddr_un_spec.rb
@@ -1,26 +1,24 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe 'Socket.unpack_sockaddr_un' do
-    it 'decodes sockaddr to unix path' do
-      sockaddr = Socket.sockaddr_un('/tmp/sock')
-      Socket.unpack_sockaddr_un(sockaddr).should == '/tmp/sock'
-    end
+describe 'Socket.unpack_sockaddr_un' do
+  it 'decodes sockaddr to unix path' do
+    sockaddr = Socket.sockaddr_un('/tmp/sock')
+    Socket.unpack_sockaddr_un(sockaddr).should == '/tmp/sock'
+  end
 
-    it 'returns unix path from a passed Addrinfo' do
-      addrinfo = Addrinfo.unix('/tmp/sock')
-      Socket.unpack_sockaddr_un(addrinfo).should == '/tmp/sock'
-    end
+  it 'returns unix path from a passed Addrinfo' do
+    addrinfo = Addrinfo.unix('/tmp/sock')
+    Socket.unpack_sockaddr_un(addrinfo).should == '/tmp/sock'
+  end
 
-    it 'raises an ArgumentError when the sa_family is not AF_UNIX' do
-      sockaddr = Socket.sockaddr_in(0, '127.0.0.1')
-      -> { Socket.unpack_sockaddr_un(sockaddr) }.should raise_error(ArgumentError)
-    end
+  it 'raises an ArgumentError when the sa_family is not AF_UNIX' do
+    sockaddr = Socket.sockaddr_in(0, '127.0.0.1')
+    -> { Socket.unpack_sockaddr_un(sockaddr) }.should raise_error(ArgumentError)
+  end
 
-    it 'raises an ArgumentError when passed addrinfo is not AF_UNIX' do
-      addrinfo = Addrinfo.tcp('127.0.0.1', 0)
-      -> { Socket.unpack_sockaddr_un(addrinfo) }.should raise_error(ArgumentError)
-    end
+  it 'raises an ArgumentError when passed addrinfo is not AF_UNIX' do
+    addrinfo = Addrinfo.tcp('127.0.0.1', 0)
+    -> { Socket.unpack_sockaddr_un(addrinfo) }.should raise_error(ArgumentError)
   end
 end
diff --git a/library/socket/spec_helper.rb b/library/socket/spec_helper.rb
index 1121542dd5..b33663e02d 100644
--- a/library/socket/spec_helper.rb
+++ b/library/socket/spec_helper.rb
@@ -2,7 +2,6 @@
 require 'socket'
 
 MSpec.enable_feature :sock_packet if Socket.const_defined?(:SOCK_PACKET)
-MSpec.enable_feature :unix_socket unless PlatformGuard.windows?
 MSpec.enable_feature :udp_cork if Socket.const_defined?(:UDP_CORK)
 MSpec.enable_feature :tcp_cork if Socket.const_defined?(:TCP_CORK)
 MSpec.enable_feature :pktinfo if Socket.const_defined?(:IP_PKTINFO)
diff --git a/library/socket/unixserver/accept_nonblock_spec.rb b/library/socket/unixserver/accept_nonblock_spec.rb
index dba3de7359..f67941b296 100644
--- a/library/socket/unixserver/accept_nonblock_spec.rb
+++ b/library/socket/unixserver/accept_nonblock_spec.rb
@@ -1,87 +1,85 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe "UNIXServer#accept_nonblock" do
-    before :each do
-      @path = SocketSpecs.socket_path
-      @server = UNIXServer.open(@path)
-      @client = UNIXSocket.open(@path)
+describe "UNIXServer#accept_nonblock" do
+  before :each do
+    @path = SocketSpecs.socket_path
+    @server = UNIXServer.open(@path)
+    @client = UNIXSocket.open(@path)
 
-      @socket = @server.accept_nonblock
-      @client.send("foobar", 0)
-    end
+    @socket = @server.accept_nonblock
+    @client.send("foobar", 0)
+  end
 
-    after :each do
-      @socket.close
-      @client.close
-      @server.close
-      SocketSpecs.rm_socket @path
-    end
+  after :each do
+    @socket.close
+    @client.close
+    @server.close
+    SocketSpecs.rm_socket @path
+  end
 
-    it "accepts a connection in a non-blocking way" do
-      data = @socket.recvfrom(6).first
-      data.should == "foobar"
-    end
+  it "accepts a connection in a non-blocking way" do
+    data = @socket.recvfrom(6).first
+    data.should == "foobar"
+  end
 
-    it "returns a UNIXSocket" do
-      @socket.should be_kind_of(UNIXSocket)
-    end
+  it "returns a UNIXSocket" do
+    @socket.should be_kind_of(UNIXSocket)
+  end
+
+  it 'returns :wait_readable in exceptionless mode' do
+    @server.accept_nonblock(exception: false).should == :wait_readable
+  end
+end
 
-    it 'returns :wait_readable in exceptionless mode' do
-      @server.accept_nonblock(exception: false).should == :wait_readable
+describe 'UNIXServer#accept_nonblock' do
+  before do
+    @path   = SocketSpecs.socket_path
+    @server = UNIXServer.new(@path)
+  end
+
+  after do
+    @server.close
+    rm_r(@path)
+  end
+
+  describe 'without a client' do
+    it 'raises IO::WaitReadable' do
+      -> { @server.accept_nonblock }.should raise_error(IO::WaitReadable)
     end
   end
 
-  describe 'UNIXServer#accept_nonblock' do
+  describe 'with a client' do
     before do
-      @path   = SocketSpecs.socket_path
-      @server = UNIXServer.new(@path)
+      @client = UNIXSocket.new(@path)
     end
 
     after do
-      @server.close
-      rm_r(@path)
+      @client.close
+      @socket.close if @socket
     end
 
-    describe 'without a client' do
-      it 'raises IO::WaitReadable' do
-        -> { @server.accept_nonblock }.should raise_error(IO::WaitReadable)
+    describe 'without any data' do
+      it 'returns a UNIXSocket' do
+        @socket = @server.accept_nonblock
+        @socket.should be_an_instance_of(UNIXSocket)
       end
     end
 
-    describe 'with a client' do
+    describe 'with data available' do
       before do
-        @client = UNIXSocket.new(@path)
-      end
-
-      after do
-        @client.close
-        @socket.close if @socket
+        @client.write('hello')
       end
 
-      describe 'without any data' do
-        it 'returns a UNIXSocket' do
-          @socket = @server.accept_nonblock
-          @socket.should be_an_instance_of(UNIXSocket)
-        end
+      it 'returns a UNIXSocket' do
+        @socket = @server.accept_nonblock
+        @socket.should be_an_instance_of(UNIXSocket)
       end
 
-      describe 'with data available' do
-        before do
-          @client.write('hello')
-        end
-
-        it 'returns a UNIXSocket' do
+      describe 'the returned UNIXSocket' do
+        it 'can read the data written' do
           @socket = @server.accept_nonblock
-          @socket.should be_an_instance_of(UNIXSocket)
-        end
-
-        describe 'the returned UNIXSocket' do
-          it 'can read the data written' do
-            @socket = @server.accept_nonblock
-            @socket.recv(5).should == 'hello'
-          end
+          @socket.recv(5).should == 'hello'
         end
       end
     end
diff --git a/library/socket/unixserver/accept_spec.rb b/library/socket/unixserver/accept_spec.rb
index 1305bc6220..cc2c922b6f 100644
--- a/library/socket/unixserver/accept_spec.rb
+++ b/library/socket/unixserver/accept_spec.rb
@@ -1,126 +1,124 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe "UNIXServer#accept" do
-    before :each do
-      @path = SocketSpecs.socket_path
-      @server = UNIXServer.open(@path)
-    end
+describe "UNIXServer#accept" do
+  before :each do
+    @path = SocketSpecs.socket_path
+    @server = UNIXServer.open(@path)
+  end
 
-    after :each do
-      @server.close if @server
-      SocketSpecs.rm_socket @path
-    end
+  after :each do
+    @server.close if @server
+    SocketSpecs.rm_socket @path
+  end
 
-    it "accepts what is written by the client" do
-      client = UNIXSocket.open(@path)
+  it "accepts what is written by the client" do
+    client = UNIXSocket.open(@path)
 
-      client.send('hello', 0)
+    client.send('hello', 0)
 
-      sock = @server.accept
-      begin
-        data, info = sock.recvfrom(5)
+    sock = @server.accept
+    begin
+      data, info = sock.recvfrom(5)
 
-        data.should == 'hello'
-        info.should_not be_empty
-      ensure
-        sock.close
-        client.close
-      end
+      data.should == 'hello'
+      info.should_not be_empty
+    ensure
+      sock.close
+      client.close
     end
+  end
 
-    it "can be interrupted by Thread#kill" do
-      t = Thread.new {
-        @server.accept
-      }
-      Thread.pass while t.status and t.status != "sleep"
-
-      # kill thread, ensure it dies in a reasonable amount of time
-      t.kill
-      a = 0
-      while t.alive? and a < 5000
-        sleep 0.001
-        a += 1
-      end
-      a.should < 5000
+  it "can be interrupted by Thread#kill" do
+    t = Thread.new {
+      @server.accept
+    }
+    Thread.pass while t.status and t.status != "sleep"
+
+    # kill thread, ensure it dies in a reasonable amount of time
+    t.kill
+    a = 0
+    while t.alive? and a < 5000
+      sleep 0.001
+      a += 1
     end
+    a.should < 5000
+  end
 
-    it "can be interrupted by Thread#raise" do
-      t = Thread.new {
-        -> {
-          @server.accept
-        }.should raise_error(Exception, "interrupted")
-      }
+  it "can be interrupted by Thread#raise" do
+    t = Thread.new {
+      -> {
+        @server.accept
+      }.should raise_error(Exception, "interrupted")
+    }
 
-      Thread.pass while t.status and t.status != "sleep"
-      t.raise Exception, "interrupted"
-      t.join
-    end
+    Thread.pass while t.status and t.status != "sleep"
+    t.raise Exception, "interrupted"
+    t.join
   end
 end
 
-with_feature :unix_socket do
-  describe 'UNIXServer#accept' do
+describe 'UNIXServer#accept' do
+  before do
+    @path = SocketSpecs.socket_path
+    @server = UNIXServer.new(@path)
+  end
+
+  after do
+    @server.close
+    rm_r(@path)
+  end
+
+  describe 'without a client' do
+    it 'blocks the calling thread' do
+      -> { @server.accept }.should block_caller
+    end
+  end
+
+  describe 'with a client' do
     before do
-      @path = SocketSpecs.socket_path
-      @server = UNIXServer.new(@path)
+      @client = UNIXSocket.new(@path)
     end
 
     after do
-      @server.close
-      rm_r(@path)
+      @client.close
+      @socket.close if @socket
     end
 
-    describe 'without a client' do
-      it 'blocks the calling thread' do
-        -> { @server.accept }.should block_caller
+    describe 'without any data' do
+      it 'returns a UNIXSocket' do
+        @socket = @server.accept
+        @socket.should be_an_instance_of(UNIXSocket)
       end
     end
 
-    describe 'with a client' do
+    describe 'with data available' do
       before do
-        @client = UNIXSocket.new(@path)
-      end
-
-      after do
-        @client.close
-        @socket.close if @socket
+        @client.write('hello')
       end
 
-      describe 'without any data' do
-        it 'returns a UNIXSocket' do
-          @socket = @server.accept
-          @socket.should be_an_instance_of(UNIXSocket)
-        end
+      it 'returns a UNIXSocket' do
+        @socket = @server.accept
+        @socket.should be_an_instance_of(UNIXSocket)
       end
 
-      describe 'with data available' do
-        before do
-          @client.write('hello')
-        end
-
-        it 'returns a UNIXSocket' do
+      describe 'the returned UNIXSocket' do
+        it 'can read the data written' do
           @socket = @server.accept
-          @socket.should be_an_instance_of(UNIXSocket)
+          @socket.recv(5).should == 'hello'
         end
 
-        describe 'the returned UNIXSocket' do
-          it 'can read the data written' do
-            @socket = @server.accept
-            @socket.recv(5).should == 'hello'
-          end
-
+        platform_is_not :windows do
           it "is set to nonblocking" do
             require 'io/nonblock'
             @socket = @server.accept
             @socket.should.nonblock?
           end
+        end
 
-          it "is set to close on exec" do
-            @socket = @server.accept
-            @socket.should.close_on_exec?
-          end
+        it "is set to close on exec" do
+          @socket = @server.accept
+          @socket.should.close_on_exec?
         end
       end
     end
diff --git a/library/socket/unixserver/for_fd_spec.rb b/library/socket/unixserver/for_fd_spec.rb
index 8cc55ef391..be1c2df4d7 100644
--- a/library/socket/unixserver/for_fd_spec.rb
+++ b/library/socket/unixserver/for_fd_spec.rb
@@ -1,23 +1,21 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe "UNIXServer.for_fd" do
-    before :each do
-      @unix_path = SocketSpecs.socket_path
-      @unix = UNIXServer.new(@unix_path)
-    end
+describe "UNIXServer.for_fd" do
+  before :each do
+    @unix_path = SocketSpecs.socket_path
+    @unix = UNIXServer.new(@unix_path)
+  end
 
-    after :each do
-      @unix.close if @unix
-      SocketSpecs.rm_socket @unix_path
-    end
+  after :each do
+    @unix.close if @unix
+    SocketSpecs.rm_socket @unix_path
+  end
 
-    it "can calculate the path" do
-      b = UNIXServer.for_fd(@unix.fileno)
-      b.autoclose = false
+  it "can calculate the path" do
+    b = UNIXServer.for_fd(@unix.fileno)
+    b.autoclose = false
 
-      b.path.should == @unix_path
-    end
+    b.path.should == @unix_path
   end
 end
diff --git a/library/socket/unixserver/initialize_spec.rb b/library/socket/unixserver/initialize_spec.rb
index 0cc49ef1eb..3728a307b0 100644
--- a/library/socket/unixserver/initialize_spec.rb
+++ b/library/socket/unixserver/initialize_spec.rb
@@ -1,28 +1,26 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe 'UNIXServer#initialize' do
-    before do
-      @path = SocketSpecs.socket_path
-      @server = UNIXServer.new(@path)
-    end
+describe 'UNIXServer#initialize' do
+  before do
+    @path = SocketSpecs.socket_path
+    @server = UNIXServer.new(@path)
+  end
 
-    after do
-      @server.close if @server
-      rm_r @path
-    end
+  after do
+    @server.close if @server
+    rm_r @path
+  end
 
-    it 'returns a new UNIXServer' do
-      @server.should be_an_instance_of(UNIXServer)
-    end
+  it 'returns a new UNIXServer' do
+    @server.should be_an_instance_of(UNIXServer)
+  end
 
-    it 'sets the socket to binmode' do
-      @server.binmode?.should be_true
-    end
+  it 'sets the socket to binmode' do
+    @server.binmode?.should be_true
+  end
 
-    it 'raises Errno::EADDRINUSE when the socket is already in use' do
-      -> { UNIXServer.new(@path) }.should raise_error(Errno::EADDRINUSE)
-    end
+  it 'raises Errno::EADDRINUSE when the socket is already in use' do
+    -> { UNIXServer.new(@path) }.should raise_error(Errno::EADDRINUSE)
   end
 end
diff --git a/library/socket/unixserver/listen_spec.rb b/library/socket/unixserver/listen_spec.rb
index b90b3bbb09..7938d648c4 100644
--- a/library/socket/unixserver/listen_spec.rb
+++ b/library/socket/unixserver/listen_spec.rb
@@ -1,21 +1,19 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe 'UNIXServer#listen' do
-    before do
-      @path   = SocketSpecs.socket_path
-      @server = UNIXServer.new(@path)
-    end
+describe 'UNIXServer#listen' do
+  before do
+    @path   = SocketSpecs.socket_path
+    @server = UNIXServer.new(@path)
+  end
 
-    after do
-      @server.close
+  after do
+    @server.close
 
-      rm_r(@path)
-    end
+    rm_r(@path)
+  end
 
-    it 'returns 0' do
-      @server.listen(1).should == 0
-    end
+  it 'returns 0' do
+    @server.listen(1).should == 0
   end
 end
diff --git a/library/socket/unixserver/new_spec.rb b/library/socket/unixserver/new_spec.rb
index a160e3ce5c..7d0c7bf76e 100644
--- a/library/socket/unixserver/new_spec.rb
+++ b/library/socket/unixserver/new_spec.rb
@@ -1,14 +1,12 @@
 require_relative '../spec_helper'
 require_relative 'shared/new'
 
-with_feature :unix_socket do
-  describe "UNIXServer.new" do
-    it_behaves_like :unixserver_new, :new
+describe "UNIXServer.new" do
+  it_behaves_like :unixserver_new, :new
 
-    it "does not use the given block and warns to use UNIXServer::open" do
-      -> {
-        @server = UNIXServer.new(@path) { raise }
-      }.should complain(/warning: UNIXServer::new\(\) does not take block; use UNIXServer::open\(\) instead/)
-    end
+  it "does not use the given block and warns to use UNIXServer::open" do
+    -> {
+      @server = UNIXServer.new(@path) { raise }
+    }.should complain(/warning: UNIXServer::new\(\) does not take block; use UNIXServer::open\(\) instead/)
   end
 end
diff --git a/library/socket/unixserver/open_spec.rb b/library/socket/unixserver/open_spec.rb
index 16453dd3bd..c49df802d0 100644
--- a/library/socket/unixserver/open_spec.rb
+++ b/library/socket/unixserver/open_spec.rb
@@ -2,25 +2,23 @@
 require_relative '../fixtures/classes'
 require_relative 'shared/new'
 
-with_feature :unix_socket do
-  describe "UNIXServer.open" do
-    it_behaves_like :unixserver_new, :open
+describe "UNIXServer.open" do
+  it_behaves_like :unixserver_new, :open
 
-    before :each do
-      @path = SocketSpecs.socket_path
-    end
+  before :each do
+    @path = SocketSpecs.socket_path
+  end
 
-    after :each do
-      @server.close if @server
-      @server = nil
-      SocketSpecs.rm_socket @path
-    end
+  after :each do
+    @server.close if @server
+    @server = nil
+    SocketSpecs.rm_socket @path
+  end
 
-    it "yields the new UNIXServer object to the block, if given" do
-      UNIXServer.open(@path) do |unix|
-        unix.path.should == @path
-        unix.addr.should == ["AF_UNIX", @path]
-      end
+  it "yields the new UNIXServer object to the block, if given" do
+    UNIXServer.open(@path) do |unix|
+      unix.path.should == @path
+      unix.addr.should == ["AF_UNIX", @path]
     end
   end
 end
diff --git a/library/socket/unixserver/sysaccept_spec.rb b/library/socket/unixserver/sysaccept_spec.rb
index e59731878a..c4a4ecc824 100644
--- a/library/socket/unixserver/sysaccept_spec.rb
+++ b/library/socket/unixserver/sysaccept_spec.rb
@@ -1,51 +1,49 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe 'UNIXServer#sysaccept' do
+describe 'UNIXServer#sysaccept' do
+  before do
+    @path   = SocketSpecs.socket_path
+    @server = UNIXServer.new(@path)
+  end
+
+  after do
+    @server.close
+
+    rm_r(@path)
+  end
+
+  describe 'without a client' do
+    it 'blocks the calling thread' do
+      -> { @server.sysaccept }.should block_caller
+    end
+  end
+
+  describe 'with a client' do
     before do
-      @path   = SocketSpecs.socket_path
-      @server = UNIXServer.new(@path)
+      @client = UNIXSocket.new(@path)
     end
 
     after do
-      @server.close
-
-      rm_r(@path)
+      Socket.for_fd(@fd).close if @fd
+      @client.close
     end
 
-    describe 'without a client' do
-      it 'blocks the calling thread' do
-        -> { @server.sysaccept }.should block_caller
+    describe 'without any data' do
+      it 'returns an Integer' do
+        @fd = @server.sysaccept
+        @fd.should be_kind_of(Integer)
       end
     end
 
-    describe 'with a client' do
+    describe 'with data available' do
       before do
-        @client = UNIXSocket.new(@path)
-      end
-
-      after do
-        Socket.for_fd(@fd).close if @fd
-        @client.close
+        @client.write('hello')
       end
 
-      describe 'without any data' do
-        it 'returns an Integer' do
-          @fd = @server.sysaccept
-          @fd.should be_kind_of(Integer)
-        end
-      end
-
-      describe 'with data available' do
-        before do
-          @client.write('hello')
-        end
-
-        it 'returns an Integer' do
-          @fd = @server.sysaccept
-          @fd.should be_kind_of(Integer)
-        end
+      it 'returns an Integer' do
+        @fd = @server.sysaccept
+        @fd.should be_kind_of(Integer)
       end
     end
   end
diff --git a/library/socket/unixsocket/addr_spec.rb b/library/socket/unixsocket/addr_spec.rb
index d93e061312..1afe9b12dc 100644
--- a/library/socket/unixsocket/addr_spec.rb
+++ b/library/socket/unixsocket/addr_spec.rb
@@ -1,35 +1,33 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe "UNIXSocket#addr" do
-    before :each do
-      @path = SocketSpecs.socket_path
-      @server = UNIXServer.open(@path)
-      @client = UNIXSocket.open(@path)
-    end
+describe "UNIXSocket#addr" do
+  before :each do
+    @path = SocketSpecs.socket_path
+    @server = UNIXServer.open(@path)
+    @client = UNIXSocket.open(@path)
+  end
 
-    after :each do
-      @client.close
-      @server.close
-      SocketSpecs.rm_socket @path
-    end
+  after :each do
+    @client.close
+    @server.close
+    SocketSpecs.rm_socket @path
+  end
 
-    it "returns an array" do
-      @client.addr.should be_kind_of(Array)
-    end
+  it "returns an array" do
+    @client.addr.should be_kind_of(Array)
+  end
 
-    it "returns the address family of this socket in an array" do
-      @client.addr[0].should == "AF_UNIX"
-      @server.addr[0].should == "AF_UNIX"
-    end
+  it "returns the address family of this socket in an array" do
+    @client.addr[0].should == "AF_UNIX"
+    @server.addr[0].should == "AF_UNIX"
+  end
 
-    it "returns the path of the socket in an array if it's a server" do
-      @server.addr[1].should == @path
-    end
+  it "returns the path of the socket in an array if it's a server" do
+    @server.addr[1].should == @path
+  end
 
-    it "returns an empty string for path if it's a client" do
-      @client.addr[1].should == ""
-    end
+  it "returns an empty string for path if it's a client" do
+    @client.addr[1].should == ""
   end
 end
diff --git a/library/socket/unixsocket/initialize_spec.rb b/library/socket/unixsocket/initialize_spec.rb
index bf7896ab0e..5dccfcc745 100644
--- a/library/socket/unixsocket/initialize_spec.rb
+++ b/library/socket/unixsocket/initialize_spec.rb
@@ -1,48 +1,56 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe 'UNIXSocket#initialize' do
-    describe 'using a non existing path' do
+describe 'UNIXSocket#initialize' do
+  describe 'using a non existing path' do
+    platform_is_not :windows do
       it 'raises Errno::ENOENT' do
         -> { UNIXSocket.new(SocketSpecs.socket_path) }.should raise_error(Errno::ENOENT)
       end
     end
 
-    describe 'using an existing socket path' do
-      before do
-        @path = SocketSpecs.socket_path
-        @server = UNIXServer.new(@path)
-        @socket = UNIXSocket.new(@path)
+    platform_is :windows do
+      # Why, Windows, why?
+      it 'raises Errno::ECONNREFUSED' do
+        -> { UNIXSocket.new(SocketSpecs.socket_path) }.should raise_error(Errno::ECONNREFUSED)
       end
+    end
+  end
 
-      after do
-        @socket.close
-        @server.close
-        rm_r(@path)
-      end
+  describe 'using an existing socket path' do
+    before do
+      @path = SocketSpecs.socket_path
+      @server = UNIXServer.new(@path)
+      @socket = UNIXSocket.new(@path)
+    end
 
-      it 'returns a new UNIXSocket' do
-        @socket.should be_an_instance_of(UNIXSocket)
-      end
+    after do
+      @socket.close
+      @server.close
+      rm_r(@path)
+    end
 
-      it 'sets the socket path to an empty String' do
-        @socket.path.should == ''
-      end
+    it 'returns a new UNIXSocket' do
+      @socket.should be_an_instance_of(UNIXSocket)
+    end
 
-      it 'sets the socket to binmode' do
-        @socket.binmode?.should be_true
-      end
+    it 'sets the socket path to an empty String' do
+      @socket.path.should == ''
+    end
+
+    it 'sets the socket to binmode' do
+      @socket.binmode?.should be_true
+    end
 
+    platform_is_not :windows do
       it 'sets the socket to nonblock' do
         require 'io/nonblock'
         @socket.should.nonblock?
       end
+    end
 
-      it 'sets the socket to close on exec' do
-        @socket.should.close_on_exec?
-      end
-
+    it 'sets the socket to close on exec' do
+      @socket.should.close_on_exec?
     end
   end
 end
diff --git a/library/socket/unixsocket/inspect_spec.rb b/library/socket/unixsocket/inspect_spec.rb
index a542ba6db5..77bb521069 100644
--- a/library/socket/unixsocket/inspect_spec.rb
+++ b/library/socket/unixsocket/inspect_spec.rb
@@ -1,17 +1,15 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe "UNIXSocket#inspect" do
-    it "returns sockets fd for unnamed sockets" do
-      begin
-        s1, s2 = UNIXSocket.socketpair
-        s1.inspect.should == "#<UNIXSocket:fd #{s1.fileno}>"
-        s2.inspect.should == "#<UNIXSocket:fd #{s2.fileno}>"
-      ensure
-        s1.close
-        s2.close
-      end
+describe "UNIXSocket#inspect" do
+  it "returns sockets fd for unnamed sockets" do
+    begin
+      s1, s2 = UNIXSocket.socketpair
+      s1.inspect.should == "#<UNIXSocket:fd #{s1.fileno}>"
+      s2.inspect.should == "#<UNIXSocket:fd #{s2.fileno}>"
+    ensure
+      s1.close
+      s2.close
     end
   end
 end
diff --git a/library/socket/unixsocket/local_address_spec.rb b/library/socket/unixsocket/local_address_spec.rb
index 734253e7f5..0fdec38293 100644
--- a/library/socket/unixsocket/local_address_spec.rb
+++ b/library/socket/unixsocket/local_address_spec.rb
@@ -1,94 +1,92 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe 'UNIXSocket#local_address' do
-    before do
-      @path   = SocketSpecs.socket_path
-      @server = UNIXServer.new(@path)
-      @client = UNIXSocket.new(@path)
-    end
+describe 'UNIXSocket#local_address' do
+  before do
+    @path   = SocketSpecs.socket_path
+    @server = UNIXServer.new(@path)
+    @client = UNIXSocket.new(@path)
+  end
 
-    after do
-      @client.close
-      @server.close
+  after do
+    @client.close
+    @server.close
 
-      rm_r(@path)
-    end
-
-    it 'returns an Addrinfo' do
-      @client.local_address.should be_an_instance_of(Addrinfo)
-    end
+    rm_r(@path)
+  end
 
-    describe 'the returned Addrinfo' do
-      platform_is_not :aix do
-        it 'uses AF_UNIX as the address family' do
-          @client.local_address.afamily.should == Socket::AF_UNIX
-        end
+  it 'returns an Addrinfo' do
+    @client.local_address.should be_an_instance_of(Addrinfo)
+  end
 
-        it 'uses PF_UNIX as the protocol family' do
-          @client.local_address.pfamily.should == Socket::PF_UNIX
-        end
+  describe 'the returned Addrinfo' do
+    platform_is_not :aix do
+      it 'uses AF_UNIX as the address family' do
+        @client.local_address.afamily.should == Socket::AF_UNIX
       end
 
-      it 'uses SOCK_STREAM as the socket type' do
-        @client.local_address.socktype.should == Socket::SOCK_STREAM
+      it 'uses PF_UNIX as the protocol family' do
+        @client.local_address.pfamily.should == Socket::PF_UNIX
       end
+    end
 
-      platform_is_not :aix do
-        it 'uses an empty socket path' do
-          @client.local_address.unix_path.should == ''
-        end
-      end
+    it 'uses SOCK_STREAM as the socket type' do
+      @client.local_address.socktype.should == Socket::SOCK_STREAM
+    end
 
-      it 'uses 0 as the protocol' do
-        @client.local_address.protocol.should == 0
+    platform_is_not :aix do
+      it 'uses an empty socket path' do
+        @client.local_address.unix_path.should == ''
       end
     end
-  end
 
-  describe 'UNIXSocket#local_address with a UNIX socket pair' do
-    before :each do
-      @sock, @sock2 = Socket.pair(Socket::AF_UNIX, Socket::SOCK_STREAM)
+    it 'uses 0 as the protocol' do
+      @client.local_address.protocol.should == 0
     end
+  end
+end
 
-    after :each do
-      @sock.close
-      @sock2.close
-    end
+describe 'UNIXSocket#local_address with a UNIX socket pair' do
+  before :each do
+    @sock, @sock2 = Socket.pair(Socket::AF_UNIX, Socket::SOCK_STREAM)
+  end
 
-    it 'returns an Addrinfo' do
-      @sock.local_address.should be_an_instance_of(Addrinfo)
-    end
+  after :each do
+    @sock.close
+    @sock2.close
+  end
 
-    describe 'the returned Addrinfo' do
-      it 'uses AF_UNIX as the address family' do
-        @sock.local_address.afamily.should == Socket::AF_UNIX
-      end
+  it 'returns an Addrinfo' do
+    @sock.local_address.should be_an_instance_of(Addrinfo)
+  end
 
-      it 'uses PF_UNIX as the protocol family' do
-        @sock.local_address.pfamily.should == Socket::PF_UNIX
-      end
+  describe 'the returned Addrinfo' do
+    it 'uses AF_UNIX as the address family' do
+      @sock.local_address.afamily.should == Socket::AF_UNIX
+    end
 
-      it 'uses SOCK_STREAM as the socket type' do
-        @sock.local_address.socktype.should == Socket::SOCK_STREAM
-      end
+    it 'uses PF_UNIX as the protocol family' do
+      @sock.local_address.pfamily.should == Socket::PF_UNIX
+    end
 
-      it 'raises SocketError for #ip_address' do
-        -> {
-          @sock.local_address.ip_address
-        }.should raise_error(SocketError, "need IPv4 or IPv6 address")
-      end
+    it 'uses SOCK_STREAM as the socket type' do
+      @sock.local_address.socktype.should == Socket::SOCK_STREAM
+    end
 
-      it 'raises SocketError for #ip_port' do
-        -> {
-          @sock.local_address.ip_port
-        }.should raise_error(SocketError, "need IPv4 or IPv6 address")
-      end
+    it 'raises SocketError for #ip_address' do
+      -> {
+        @sock.local_address.ip_address
+      }.should raise_error(SocketError, "need IPv4 or IPv6 address")
+    end
 
-      it 'uses 0 as the protocol' do
-        @sock.local_address.protocol.should == 0
-      end
+    it 'raises SocketError for #ip_port' do
+      -> {
+        @sock.local_address.ip_port
+      }.should raise_error(SocketError, "need IPv4 or IPv6 address")
+    end
+
+    it 'uses 0 as the protocol' do
+      @sock.local_address.protocol.should == 0
     end
   end
 end
diff --git a/library/socket/unixsocket/new_spec.rb b/library/socket/unixsocket/new_spec.rb
index 6d8ea6dcfe..fea2c1e2b7 100644
--- a/library/socket/unixsocket/new_spec.rb
+++ b/library/socket/unixsocket/new_spec.rb
@@ -1,14 +1,12 @@
 require_relative '../spec_helper'
 require_relative 'shared/new'
 
-with_feature :unix_socket do
-  describe "UNIXSocket.new" do
-    it_behaves_like :unixsocket_new, :new
+describe "UNIXSocket.new" do
+  it_behaves_like :unixsocket_new, :new
 
-    it "does not use the given block and warns to use UNIXSocket::open" do
-      -> {
-        @client = UNIXSocket.new(@path) { raise }
-      }.should complain(/warning: UNIXSocket::new\(\) does not take block; use UNIXSocket::open\(\) instead/)
-    end
+  it "does not use the given block and warns to use UNIXSocket::open" do
+    -> {
+      @client = UNIXSocket.new(@path) { raise }
+    }.should complain(/warning: UNIXSocket::new\(\) does not take block; use UNIXSocket::open\(\) instead/)
   end
 end
diff --git a/library/socket/unixsocket/open_spec.rb b/library/socket/unixsocket/open_spec.rb
index 61def30abb..b5e8c6c23a 100644
--- a/library/socket/unixsocket/open_spec.rb
+++ b/library/socket/unixsocket/open_spec.rb
@@ -2,27 +2,25 @@
 require_relative '../fixtures/classes'
 require_relative 'shared/new'
 
-with_feature :unix_socket do
-  describe "UNIXSocket.open" do
-    it_behaves_like :unixsocket_new, :open
-  end
+describe "UNIXSocket.open" do
+  it_behaves_like :unixsocket_new, :open
+end
 
-  describe "UNIXSocket.open" do
-    before :each do
-      @path = SocketSpecs.socket_path
-      @server = UNIXServer.open(@path)
-    end
+describe "UNIXSocket.open" do
+  before :each do
+    @path = SocketSpecs.socket_path
+    @server = UNIXServer.open(@path)
+  end
 
-    after :each do
-      @server.close
-      SocketSpecs.rm_socket @path
-    end
+  after :each do
+    @server.close
+    SocketSpecs.rm_socket @path
+  end
 
-    it "opens a unix socket on the specified file and yields it to the block" do
-      UNIXSocket.open(@path) do |client|
-        client.addr[0].should == "AF_UNIX"
-        client.should_not.closed?
-      end
+  it "opens a unix socket on the specified file and yields it to the block" do
+    UNIXSocket.open(@path) do |client|
+      client.addr[0].should == "AF_UNIX"
+      client.should_not.closed?
     end
   end
 end
diff --git a/library/socket/unixsocket/pair_spec.rb b/library/socket/unixsocket/pair_spec.rb
index b0a3b2af99..9690142668 100644
--- a/library/socket/unixsocket/pair_spec.rb
+++ b/library/socket/unixsocket/pair_spec.rb
@@ -3,18 +3,16 @@
 require_relative '../shared/partially_closable_sockets'
 require_relative 'shared/pair'
 
-with_feature :unix_socket do
-  describe "UNIXSocket.pair" do
-    it_should_behave_like :unixsocket_pair
-    it_should_behave_like :partially_closable_sockets
+describe "UNIXSocket.pair" do
+  it_should_behave_like :unixsocket_pair
+  it_should_behave_like :partially_closable_sockets
 
-    before :each do
-      @s1, @s2 = UNIXSocket.pair
-    end
+  before :each do
+    @s1, @s2 = UNIXSocket.pair
+  end
 
-    after :each do
-      @s1.close
-      @s2.close
-    end
+  after :each do
+    @s1.close
+    @s2.close
   end
 end
diff --git a/library/socket/unixsocket/partially_closable_spec.rb b/library/socket/unixsocket/partially_closable_spec.rb
index ef7d0f0b2a..108a6c3063 100644
--- a/library/socket/unixsocket/partially_closable_spec.rb
+++ b/library/socket/unixsocket/partially_closable_spec.rb
@@ -2,22 +2,20 @@
 require_relative '../fixtures/classes'
 require_relative '../shared/partially_closable_sockets'
 
-with_feature :unix_socket do
-  describe "UNIXSocket partial closability" do
-    before :each do
-      @path = SocketSpecs.socket_path
-      @server = UNIXServer.open(@path)
-      @s1 = UNIXSocket.new(@path)
-      @s2 = @server.accept
-    end
-
-    after :each do
-      @server.close
-      @s1.close
-      @s2.close
-      SocketSpecs.rm_socket @path
-    end
+describe "UNIXSocket partial closability" do
+  before :each do
+    @path = SocketSpecs.socket_path
+    @server = UNIXServer.open(@path)
+    @s1 = UNIXSocket.new(@path)
+    @s2 = @server.accept
+  end
 
-    it_should_behave_like :partially_closable_sockets
+  after :each do
+    @server.close
+    @s1.close
+    @s2.close
+    SocketSpecs.rm_socket @path
   end
+
+  it_should_behave_like :partially_closable_sockets
 end
diff --git a/library/socket/unixsocket/path_spec.rb b/library/socket/unixsocket/path_spec.rb
index a608378e4f..ffe7e4bea2 100644
--- a/library/socket/unixsocket/path_spec.rb
+++ b/library/socket/unixsocket/path_spec.rb
@@ -1,26 +1,24 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe "UNIXSocket#path" do
-    before :each do
-      @path = SocketSpecs.socket_path
-      @server = UNIXServer.open(@path)
-      @client = UNIXSocket.open(@path)
-    end
+describe "UNIXSocket#path" do
+  before :each do
+    @path = SocketSpecs.socket_path
+    @server = UNIXServer.open(@path)
+    @client = UNIXSocket.open(@path)
+  end
 
-    after :each do
-      @client.close
-      @server.close
-      SocketSpecs.rm_socket @path
-    end
+  after :each do
+    @client.close
+    @server.close
+    SocketSpecs.rm_socket @path
+  end
 
-    it "returns the path of the socket if it's a server" do
-      @server.path.should == @path
-    end
+  it "returns the path of the socket if it's a server" do
+    @server.path.should == @path
+  end
 
-    it "returns an empty string for path if it's a client" do
-      @client.path.should == ""
-    end
+  it "returns an empty string for path if it's a client" do
+    @client.path.should == ""
   end
 end
diff --git a/library/socket/unixsocket/peeraddr_spec.rb b/library/socket/unixsocket/peeraddr_spec.rb
index 72bc96b1fe..10cab13b42 100644
--- a/library/socket/unixsocket/peeraddr_spec.rb
+++ b/library/socket/unixsocket/peeraddr_spec.rb
@@ -1,28 +1,26 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe "UNIXSocket#peeraddr" do
-    before :each do
-      @path = SocketSpecs.socket_path
-      @server = UNIXServer.open(@path)
-      @client = UNIXSocket.open(@path)
-    end
+describe "UNIXSocket#peeraddr" do
+  before :each do
+    @path = SocketSpecs.socket_path
+    @server = UNIXServer.open(@path)
+    @client = UNIXSocket.open(@path)
+  end
 
-    after :each do
-      @client.close
-      @server.close
-      SocketSpecs.rm_socket @path
-    end
+  after :each do
+    @client.close
+    @server.close
+    SocketSpecs.rm_socket @path
+  end
 
-    it "returns the address family and path of the server end of the connection" do
-      @client.peeraddr.should == ["AF_UNIX", @path]
-    end
+  it "returns the address family and path of the server end of the connection" do
+    @client.peeraddr.should == ["AF_UNIX", @path]
+  end
 
-    it "raises an error in server sockets" do
-      -> {
-        @server.peeraddr
-      }.should raise_error(Errno::ENOTCONN)
-    end
+  it "raises an error in server sockets" do
+    -> {
+      @server.peeraddr
+    }.should raise_error(Errno::ENOTCONN)
   end
 end
diff --git a/library/socket/unixsocket/recv_io_spec.rb b/library/socket/unixsocket/recv_io_spec.rb
index 1dbc4538e3..f0b408f309 100644
--- a/library/socket/unixsocket/recv_io_spec.rb
+++ b/library/socket/unixsocket/recv_io_spec.rb
@@ -1,7 +1,7 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
+platform_is_not :windows do
   describe "UNIXSocket#recv_io" do
     before :each do
       @path = SocketSpecs.socket_path
diff --git a/library/socket/unixsocket/recvfrom_spec.rb b/library/socket/unixsocket/recvfrom_spec.rb
index d849fdc302..7fa5c9b600 100644
--- a/library/socket/unixsocket/recvfrom_spec.rb
+++ b/library/socket/unixsocket/recvfrom_spec.rb
@@ -1,59 +1,105 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe "UNIXSocket#recvfrom" do
-    before :each do
-      @path = SocketSpecs.socket_path
-      @server = UNIXServer.open(@path)
-      @client = UNIXSocket.open(@path)
+describe "UNIXSocket#recvfrom" do
+  before :each do
+    @path = SocketSpecs.socket_path
+    @server = UNIXServer.open(@path)
+    @client = UNIXSocket.open(@path)
+  end
+
+  after :each do
+    @client.close
+    @server.close
+    SocketSpecs.rm_socket @path
+  end
+
+  it "receives len bytes from sock, returning an array containing sent data as first element" do
+    @client.send("foobar", 0)
+    sock = @server.accept
+    sock.recvfrom(6).first.should == "foobar"
+    sock.close
+  end
+
+  context "when called on a server's socket" do
+    platform_is_not :windows do
+      it "returns an array containing basic information on the client as second element" do
+        @client.send("foobar", 0)
+        sock = @server.accept
+        data = sock.recvfrom(6)
+        data.last.should == ["AF_UNIX", ""]
+        sock.close
+      end
     end
 
-    after :each do
-      @client.close
-      @server.close
-      SocketSpecs.rm_socket @path
+    guard -> { platform_is :windows and ruby_bug "#21702", ""..."4.0" } do
+      it "returns an array containing basic information on the client as second element" do
+        @client.send("foobar", 0)
+        sock = @server.accept
+        data = sock.recvfrom(6)
+        data.last.should == ["AF_UNIX", ""]
+        sock.close
+      end
     end
+  end
 
-    it "receives len bytes from sock" do
-      @client.send("foobar", 0)
-      sock = @server.accept
-      sock.recvfrom(6).first.should == "foobar"
-      sock.close
+  context "when called on a client's socket" do
+    platform_is_not :windows, :darwin do
+      it "returns an array containing server's address as second element" do
+        @client.send("", 0)
+        sock = @server.accept
+        sock.send("barfoo", 0)
+        @client.recvfrom(6).last.should == ["AF_UNIX", @server.local_address.unix_path]
+        sock.close
+      end
     end
 
-    it "returns an array with data and information on the sender" do
-      @client.send("foobar", 0)
-      sock = @server.accept
-      data = sock.recvfrom(6)
-      data.first.should == "foobar"
-      data.last.should == ["AF_UNIX", ""]
-      sock.close
+    guard -> { platform_is :windows and ruby_bug "#21702", ""..."4.0" } do
+      it "returns an array containing server's address as second element" do
+        @client.send("", 0)
+        sock = @server.accept
+        sock.send("barfoo", 0)
+        # This may not be correct, depends on what underlying recvfrom actually returns.
+        @client.recvfrom(6).last.should == ["AF_UNIX", @server.local_address.unix_path]
+        sock.close
+      end
     end
 
-    it "allows an output buffer as third argument" do
-      buffer = +''
+    platform_is :darwin do
+      it "returns an array containing basic information on the server as second element" do
+        @client.send("", 0)
+        sock = @server.accept
+        sock.send("barfoo", 0)
+        @client.recvfrom(6).last.should == ["AF_UNIX", ""]
+        sock.close
+      end
+    end
+  end
 
-      @client.send("foobar", 0)
-      sock = @server.accept
-      message, = sock.recvfrom(6, 0, buffer)
-      sock.close
+  it "allows an output buffer as third argument" do
+    buffer = +''
 
-      message.should.equal?(buffer)
-      buffer.should == "foobar"
-    end
+    @client.send("foobar", 0)
+    sock = @server.accept
+    message, = sock.recvfrom(6, 0, buffer)
+    sock.close
 
-    it "preserves the encoding of the given buffer" do
-      buffer = ''.encode(Encoding::ISO_8859_1)
+    message.should.equal?(buffer)
+    buffer.should == "foobar"
+  end
 
-      @client.send("foobar", 0)
-      sock = @server.accept
-      sock.recvfrom(6, 0, buffer)
-      sock.close
+  it "preserves the encoding of the given buffer" do
+    buffer = ''.encode(Encoding::ISO_8859_1)
 
-      buffer.encoding.should == Encoding::ISO_8859_1
-    end
+    @client.send("foobar", 0)
+    sock = @server.accept
+    sock.recvfrom(6, 0, buffer)
+    sock.close
 
+    buffer.encoding.should == Encoding::ISO_8859_1
+  end
+
+  platform_is_not :windows do
     it "uses different message options" do
       @client.send("foobar", Socket::MSG_PEEK)
       sock = @server.accept
@@ -65,24 +111,34 @@
       sock.close
     end
   end
+end
 
-  describe 'UNIXSocket#recvfrom' do
-    describe 'using a socket pair' do
-      before do
-        @client, @server = UNIXSocket.socketpair
-        @client.write('hello')
-      end
+describe 'UNIXSocket#recvfrom' do
+  describe 'using a socket pair' do
+    before do
+      @client, @server = UNIXSocket.socketpair
+      @client.write('hello')
+    end
 
-      after do
-        @client.close
-        @server.close
+    after do
+      @client.close
+      @server.close
+    end
+
+    platform_is_not :windows do
+      it 'returns an Array containing the data and address information' do
+        @server.recvfrom(5).should == ['hello', ['AF_UNIX', '']]
       end
+    end
 
+    guard -> { platform_is :windows and ruby_bug "#21702", ""..."4.0" } do
       it 'returns an Array containing the data and address information' do
         @server.recvfrom(5).should == ['hello', ['AF_UNIX', '']]
       end
     end
+  end
 
+  platform_is_not :windows do
     # These specs are taken from the rdoc examples on UNIXSocket#recvfrom.
     describe 'using a UNIX socket constructed using UNIXSocket.for_fd' do
       before do
diff --git a/library/socket/unixsocket/remote_address_spec.rb b/library/socket/unixsocket/remote_address_spec.rb
index 0b416254d0..84bdff0a6a 100644
--- a/library/socket/unixsocket/remote_address_spec.rb
+++ b/library/socket/unixsocket/remote_address_spec.rb
@@ -1,45 +1,43 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
-  describe 'UNIXSocket#remote_address' do
-    before do
-      @path   = SocketSpecs.socket_path
-      @server = UNIXServer.new(@path)
-      @client = UNIXSocket.new(@path)
-    end
+describe 'UNIXSocket#remote_address' do
+  before do
+    @path   = SocketSpecs.socket_path
+    @server = UNIXServer.new(@path)
+    @client = UNIXSocket.new(@path)
+  end
 
-    after do
-      @client.close
-      @server.close
+  after do
+    @client.close
+    @server.close
 
-      rm_r(@path)
-    end
+    rm_r(@path)
+  end
 
-    it 'returns an Addrinfo' do
-      @client.remote_address.should be_an_instance_of(Addrinfo)
-    end
+  it 'returns an Addrinfo' do
+    @client.remote_address.should be_an_instance_of(Addrinfo)
+  end
 
-    describe 'the returned Addrinfo' do
-      it 'uses AF_UNIX as the address family' do
-        @client.remote_address.afamily.should == Socket::AF_UNIX
-      end
+  describe 'the returned Addrinfo' do
+    it 'uses AF_UNIX as the address family' do
+      @client.remote_address.afamily.should == Socket::AF_UNIX
+    end
 
-      it 'uses PF_UNIX as the protocol family' do
-        @client.remote_address.pfamily.should == Socket::PF_UNIX
-      end
+    it 'uses PF_UNIX as the protocol family' do
+      @client.remote_address.pfamily.should == Socket::PF_UNIX
+    end
 
-      it 'uses SOCK_STREAM as the socket type' do
-        @client.remote_address.socktype.should == Socket::SOCK_STREAM
-      end
+    it 'uses SOCK_STREAM as the socket type' do
+      @client.remote_address.socktype.should == Socket::SOCK_STREAM
+    end
 
-      it 'uses the correct socket path' do
-        @client.remote_address.unix_path.should == @path
-      end
+    it 'uses the correct socket path' do
+      @client.remote_address.unix_path.should == @path
+    end
 
-      it 'uses 0 as the protocol' do
-        @client.remote_address.protocol.should == 0
-      end
+    it 'uses 0 as the protocol' do
+      @client.remote_address.protocol.should == 0
     end
   end
 end
diff --git a/library/socket/unixsocket/send_io_spec.rb b/library/socket/unixsocket/send_io_spec.rb
index 80f3550c6d..52186ec3cf 100644
--- a/library/socket/unixsocket/send_io_spec.rb
+++ b/library/socket/unixsocket/send_io_spec.rb
@@ -1,7 +1,7 @@
 require_relative '../spec_helper'
 require_relative '../fixtures/classes'
 
-with_feature :unix_socket do
+platform_is_not :windows do
   describe "UNIXSocket#send_io" do
     before :each do
       @path = SocketSpecs.socket_path
diff --git a/library/socket/unixsocket/shared/pair.rb b/library/socket/unixsocket/shared/pair.rb
index ade7fc9852..0f1af43b25 100644
--- a/library/socket/unixsocket/shared/pair.rb
+++ b/library/socket/unixsocket/shared/pair.rb
@@ -12,18 +12,37 @@
     @s2.gets.should == "foo\n"
   end
 
-  it "sets the socket paths to empty Strings" do
-    @s1.path.should == ""
-    @s2.path.should == ""
-  end
+  platform_is_not :windows do
+    it "sets the socket paths to empty Strings" do
+      @s1.path.should == ""
+      @s2.path.should == ""
+    end
+
+    it "sets the socket addresses to empty Strings" do
+      @s1.addr.should == ["AF_UNIX", ""]
+      @s2.addr.should == ["AF_UNIX", ""]
+    end
 
-  it "sets the socket addresses to empty Strings" do
-    @s1.addr.should == ["AF_UNIX", ""]
-    @s2.addr.should == ["AF_UNIX", ""]
+    it "sets the socket peer addresses to empty Strings" do
+      @s1.peeraddr.should == ["AF_UNIX", ""]
+      @s2.peeraddr.should == ["AF_UNIX", ""]
+    end
   end
 
-  it "sets the socket peer addresses to empty Strings" do
-    @s1.peeraddr.should == ["AF_UNIX", ""]
-    @s2.peeraddr.should == ["AF_UNIX", ""]
+  platform_is :windows do
+    it "emulates unnamed sockets with a temporary file with a path" do
+      @s1.path.match?(/\\AppData\\Local\\Temp\\\d+-\d+\.\(\$\)\z/).should be_true
+      @s1.addr.should == ["AF_UNIX", @s1.path]
+      @s2.peeraddr.should == ["AF_UNIX", @s1.path]
+    end
+
+    it "sets the peer address of first socket to an empty string" do
+      @s1.peeraddr.should == ["AF_UNIX", ""]
+    end
+
+    it "sets the address and path of second socket to an empty string" do
+      @s2.addr.should == ["AF_UNIX", ""]
+      @s2.path.should == ""
+    end
   end
 end
diff --git a/library/socket/unixsocket/socketpair_spec.rb b/library/socket/unixsocket/socketpair_spec.rb
index 5f34008df3..c61fc00be4 100644
--- a/library/socket/unixsocket/socketpair_spec.rb
+++ b/library/socket/unixsocket/socketpair_spec.rb
@@ -3,18 +3,16 @@
 require_relative '../shared/partially_closable_sockets'
 require_relative 'shared/pair'
 
-with_feature :unix_socket do
-  describe "UNIXSocket.socketpair" do
-    it_should_behave_like :unixsocket_pair
-    it_should_behave_like :partially_closable_sockets
+describe "UNIXSocket.socketpair" do
+  it_should_behave_like :unixsocket_pair
+  it_should_behave_like :partially_closable_sockets
 
-    before :each do
-      @s1, @s2 = UNIXSocket.socketpair
-    end
+  before :each do
+    @s1, @s2 = UNIXSocket.socketpair
+  end
 
-    after :each do
-      @s1.close
-      @s2.close
-    end
+  after :each do
+    @s1.close
+    @s2.close
   end
 end
diff --git a/shared/file/socket.rb b/shared/file/socket.rb
index 55a1cfd284..ef6c482d1c 100644
--- a/shared/file/socket.rb
+++ b/shared/file/socket.rb
@@ -1,3 +1,33 @@
 describe :file_socket, shared: true do
-  it "accepts an object that has a #to_path method"
+  it "returns false if the file is not a socket" do
+    filename = tmp("i_exist")
+    touch(filename)
+
+    @object.send(@method, filename).should == false
+
+    rm_r filename
+  end
+
+  it "returns true if the file is a socket" do
+    require 'socket'
+
+    # We need a really short name here.
+    # On Linux the path length is limited to 107, see unix(7).
+    name = tmp("s")
+    server = UNIXServer.new(name)
+
+    @object.send(@method, name).should == true
+
+    server.close
+    rm_r name
+  end
+
+  it "accepts an object that has a #to_path method" do
+    obj = Object.new
+    def obj.to_path
+      __FILE__
+    end
+
+    @object.send(@method, obj).should == false
+  end
 end