How to add content to the bottom of every post in WordPress?

Add the custom content to the bottom of every post in WordPess. 

Here is the simple plugin which will add content to the bottom 

of every post.

<?php
/*
  Plugin Name: Bottom of every post
  Plugin URI: http://www.umbrellastudio.com/wordpress/bottom-of-every-post/
  Description: Add some content to the bottom of each post.
  Version: 1.0
  Author: Corey Salzano
  Author URI: http://profiles.wordpress.org/users/salzano/
  License: GPL2
*/


/* To avoid a name collision, make sure this function is not
 already defined */

if( !function_exists("bottom_of_every_post")){
 function bottom_of_every_post($content){

 /* there is a text file in the same directory as this script */

  $fileName = dirname(__FILE__) ."/bottom_of_every_post.txt";

 /* we want to change `the_content` of posts, not pages
  and the text file must exist for this to work */

  if( !is_page( ) && file_exists( $fileName )){

  /* open the text file and read its contents */

   $theFile = fopen( $fileName, "r");
   $msg = fread( $theFile, filesize( $fileName ));
   fclose( $theFile );

  /* append the text file contents to the end of `the_content` */
   return $content . stripslashes( $msg );
  } else{

  /* if `the_content` belongs to a page or our file is missing
   the result of this filter is no change to `the_content` */

   return $content;
  }
 }

 /* add our filter function to the hook */

 add_filter('the_content', 'bottom_of_every_post');
}

?>

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