1 files changed, 32 insertions, 0 deletions
diff --git a/spec/ruby/core/io/ioctl_spec.rb b/spec/ruby/core/io/ioctl_spec.rb
new file mode 100644
index 0000000000..15a5d6ec22
--- /dev/null
+++ b/spec/ruby/core/io/ioctl_spec.rb
@@ -0,0 +1,32 @@
+require_relative '../../spec_helper'
+require_relative 'fixtures/classes'
+
+describe "IO#ioctl" do
+  platform_is_not :windows do
+    it "raises IOError on closed stream" do
+      -> { IOSpecs.closed_io.ioctl(5, 5) }.should.raise(IOError)
+    end
+  end
+
+  platform_is :linux do
+    guard -> { RUBY_PLATFORM.include?("86") } do # x86 / x86_64
+      it "resizes an empty String to match the output size" do
+        File.open(__FILE__, 'r') do |f|
+          buffer = +''
+          # FIONREAD in /usr/include/asm-generic/ioctls.h
+          f.ioctl 0x541B, buffer
+          buffer.unpack('I').first.should.is_a?(Integer)
+        end
+      end
+    end
+
+    it "raises a system call error when ioctl fails" do
+      File.open(__FILE__, 'r') do |f|
+        -> {
+          # TIOCGWINSZ in /usr/include/asm-generic/ioctls.h
+          f.ioctl 0x5413, nil
+        }.should.raise(SystemCallError)
+      end
+    end
+  end
+end