diff --git a/system/database/DB_cache.php b/system/database/DB_cache.php
index 14f3c21..ba91103 100644
--- a/system/database/DB_cache.php
+++ b/system/database/DB_cache.php
@@ -99,7 +99,7 @@
 		$segment_two = ($this->CI->uri->segment(2) == FALSE) ? 'index' : $this->CI->uri->segment(2);
 		$filepath = $this->db->cachedir.$segment_one.'+'.$segment_two.'/'.md5($sql);
 
-		if (FALSE === ($cachedata = read_file($filepath)))
+		if (FALSE === ($cachedata = file_get_contents($filepath)))
 		{
 			return FALSE;
 		}
diff --git a/system/helpers/file_helper.php b/system/helpers/file_helper.php
index d53d986..b717aaa 100644
--- a/system/helpers/file_helper.php
+++ b/system/helpers/file_helper.php
@@ -44,38 +44,15 @@
 	 *
 	 * Opens the file specfied in the path and returns it as a string.
 	 *
+	 * This function is DEPRECATED and should be removed in
+	 * CodeIgniter 3.1+. Use file_get_contents() instead.
+	 *
 	 * @param	string	path to file
 	 * @return	string
 	 */
 	function read_file($file)
 	{
-		if ( ! file_exists($file))
-		{
-			return FALSE;
-		}
-
-		if (function_exists('file_get_contents'))
-		{
-			return file_get_contents($file);
-		}
-
-		if ( ! $fp = @fopen($file, FOPEN_READ))
-		{
-			return FALSE;
-		}
-
-		flock($fp, LOCK_SH);
-
-		$data = '';
-		if (filesize($file) > 0)
-		{
-			$data =& fread($fp, filesize($file));
-		}
-
-		flock($fp, LOCK_UN);
-		fclose($fp);
-
-		return $data;
+		return file_get_contents($file);
 	}
 }
 
diff --git a/system/helpers/security_helper.php b/system/helpers/security_helper.php
index 6187a4a..3e6e914 100644
--- a/system/helpers/security_helper.php
+++ b/system/helpers/security_helper.php
@@ -77,6 +77,9 @@
 	/**
 	 * Hash encode a string
 	 *
+	 * This function is DEPRECATED and should be removed in
+	 * CodeIgniter 3.1+. Use hash() instead.
+	 *
 	 * @param	string
 	 * @param	string
 	 * @return	string
diff --git a/system/libraries/Cache/drivers/Cache_file.php b/system/libraries/Cache/drivers/Cache_file.php
index ce2c2b1..5170de8 100644
--- a/system/libraries/Cache/drivers/Cache_file.php
+++ b/system/libraries/Cache/drivers/Cache_file.php
@@ -71,7 +71,7 @@
 			return FALSE;
 		}
 
-		$data = unserialize(read_file($this->_cache_path.$id));
+		$data = unserialize(file_get_contents($this->_cache_path.$id));
 
 		if (time() >  $data['time'] + $data['ttl'])
 		{
@@ -165,7 +165,7 @@
 			return FALSE;
 		}
 
-		$data = unserialize(read_file($this->_cache_path.$id));
+		$data = unserialize(file_get_contents($this->_cache_path.$id));
 
 		if (is_array($data))
 		{