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+############
+Output Class
+############
+
+The Output class is a small class with one main function: To send the
+finalized web page to the requesting browser. It is also responsible for
+:doc:`caching <../general/caching>` your web pages, if you use that
+feature.
+
+.. note:: This class is initialized automatically by the system so there
+ is no need to do it manually.
+
+Under normal circumstances you won't even notice the Output class since
+it works transparently without your intervention. For example, when you
+use the :doc:`Loader <../libraries/loader>` class to load a view file,
+it's automatically passed to the Output class, which will be called
+automatically by CodeIgniter at the end of system execution. It is
+possible, however, for you to manually intervene with the output if you
+need to, using either of the two following functions:
+
+$this->output->set_output();
+=============================
+
+Permits you to manually set the final output string. Usage example::
+
+ $this->output->set_output($data);
+
+.. important:: If you do set your output manually, it must be the last
+ thing done in the function you call it from. For example, if you build a
+ page in one of your controller functions, don't set the output until the
+ end.
+
+$this->output->set_content_type();
+====================================
+
+Permits you to set the mime-type of your page so you can serve JSON
+data, JPEG's, XML, etc easily.
+
+::
+
+ $this->output
+ ->set_content_type('application/json')
+ ->set_output(json_encode(array('foo' => 'bar')));
+
+ $this->output
+ ->set_content_type('jpeg') // You could also use ".jpeg" which will have the full stop removed before looking in config/mimes.php
+ ->set_output(file_get_contents('files/something.jpg'));
+
+.. important:: Make sure any non-mime string you pass to this method
+ exists in config/mimes.php or it will have no effect.
+
+$this->output->get_output();
+=============================
+
+Permits you to manually retrieve any output that has been sent for
+storage in the output class. Usage example::
+
+ $string = $this->output->get_output();
+
+Note that data will only be retrievable from this function if it has
+been previously sent to the output class by one of the CodeIgniter
+functions like $this->load->view().
+
+$this->output->append_output();
+================================
+
+Appends data onto the output string. Usage example::
+
+ $this->output->append_output($data);
+
+$this->output->set_header();
+=============================
+
+Permits you to manually set server headers, which the output class will
+send for you when outputting the final rendered display. Example::
+
+ $this->output->set_header("HTTP/1.0 200 OK");
+ $this->output->set_header("HTTP/1.1 200 OK");
+ $this->output->set_header('Last-Modified: '.gmdate('D, d M Y H:i:s', $last_update).' GMT');
+ $this->output->set_header("Cache-Control: no-store, no-cache, must-revalidate");
+ $this->output->set_header("Cache-Control: post-check=0, pre-check=0");
+ $this->output->set_header("Pragma: no-cache");
+
+$this->output->set_status_header(code, 'text');
+=================================================
+
+Permits you to manually set a server status header. Example::
+
+ $this->output->set_status_header('401');
+ // Sets the header as: Unauthorized
+
+`See here <http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html>`_ for
+a full list of headers.
+
+$this->output->enable_profiler();
+==================================
+
+Permits you to enable/disable the
+:doc:`Profiler <../general/profiling>`, which will display benchmark
+and other data at the bottom of your pages for debugging and
+optimization purposes.
+
+To enable the profiler place the following function anywhere within your
+:doc:`Controller <../general/controllers>` functions::
+
+ $this->output->enable_profiler(TRUE);
+
+When enabled a report will be generated and inserted at the bottom of
+your pages.
+
+To disable the profiler you will use::
+
+ $this->output->enable_profiler(FALSE);
+
+$this->output->set_profiler_sections();
+=========================================
+
+Permits you to enable/disable specific sections of the Profiler when
+enabled. Please refer to the :doc:`Profiler <../general/profiling>`
+documentation for further information.
+
+$this->output->cache();
+=======================
+
+The CodeIgniter output library also controls caching. For more
+information, please see the :doc:`caching
+documentation <../general/caching>`.
+
+Parsing Execution Variables
+===========================
+
+CodeIgniter will parse the pseudo-variables {elapsed_time} and
+{memory_usage} in your output by default. To disable this, set the
+$parse_exec_vars class property to FALSE in your controller.
+::
+
+ $this->output->parse_exec_vars = FALSE;
+