diff --git a/dir2cast.php b/dir2cast.php
index 4ff8af7..e2f298c 100644
--- a/dir2cast.php
+++ b/dir2cast.php
@@ -617,7 +617,7 @@ protected function stripBasePath($filename)
     {
         if(strlen(RSS_File_Item::$FILES_DIR) && strpos($filename, RSS_File_Item::$FILES_DIR) === 0)
         {
-            return ltrim(substr($filename, strlen(RSS_File_Item::$FILES_DIR)), '/');
+            $filename = ltrim(substr($filename, strlen(RSS_File_Item::$FILES_DIR)), '/');
         }
         return $filename;
     }
@@ -1583,7 +1583,7 @@ public static function display($message, $errfile, $errline)
     {    
         if(self::$errors)
         {
-            if(!defined('CLI_ONLY') || !CLI_ONLY)
+            if(!defined('CLI_ONLY'))
             {
                 if(!http_response_code())
                 {
@@ -1591,12 +1591,12 @@ public static function display($message, $errfile, $errline)
                 }
             }
 
-            if((!defined('CLI_ONLY') || !CLI_ONLY) && !ini_get('html_errors'))
+            if((!defined('CLI_ONLY')) && !ini_get('html_errors'))
             {
                 header("Content-type: text/plain"); // reset the content-type
             }
 
-            if((!defined('CLI_ONLY') || !CLI_ONLY ) && ini_get('html_errors'))
+            if((!defined('CLI_ONLY')) && ini_get('html_errors'))
             {
                 header("Content-type: text/html"); // reset the content-type
                         
@@ -1650,7 +1650,7 @@ public static function display($message, $errfile, $errline)
 
     public static function display404($message)
     {
-        if(defined('CLI_ONLY') && CLI_ONLY)
+        if(defined('CLI_ONLY'))
         {
             http_response_code(404);
             header("Content-type: text/plain");
@@ -1692,18 +1692,18 @@ public static function bootstrap(array $SERVER, array $GET, array $argv)
             define('CLI_ONLY', true);
         }
 
-        if(defined('CLI_ONLY') && CLI_ONLY) {
-            define('DIR2CAST_BASE', realpath(dirname($argv[0])));
+        if(defined('CLI_ONLY')) {
+            define('DIR2CAST_BASE', slashdir(realpath(dirname($argv[0]))));
         } else {
-            define('DIR2CAST_BASE', dirname(__FILE__));
+            define('DIR2CAST_BASE', slashdir(dirname(__FILE__)));
         }
 
         // If an installation-wide config file exists, load it now.
         // Installation-wide config can contain TMP_DIR, MP3_DIR and MIN_CACHE_TIME.
         // Anything else it contains will be used as a fall-back if no dir-specific dir2cast.ini exists
-        if(file_exists( DIR2CAST_BASE . '/dir2cast.ini' ))
+        if(file_exists( DIR2CAST_BASE . 'dir2cast.ini' ))
         {
-            $ini_file_name = DIR2CAST_BASE . '/dir2cast.ini';
+            $ini_file_name = DIR2CAST_BASE . 'dir2cast.ini';
             self::load_from_ini( $ini_file_name );
             self::finalize(array('TMP_DIR', 'MP3_BASE', 'MP3_DIR', 'MIN_CACHE_TIME', 'FORCE_PASSWORD'));
             define('INI_FILE', $ini_file_name);
@@ -1725,11 +1725,12 @@ public static function bootstrap(array $SERVER, array $GET, array $argv)
             }
             if(!defined('MP3_DIR') && !empty($cli_options['media-dir']))
             {
-                define('MP3_DIR', realpath($cli_options['media-dir']));
-                if(!is_dir(MP3_DIR) or !is_readable(MP3_DIR))
+
+                if(!is_dir($cli_options['media-dir']) or !is_readable($cli_options['media-dir']))
                 {
                     ErrorHandler::display404($cli_options['media-dir']);
                 }
+                define('MP3_DIR', slashdir(realpath($cli_options['media-dir'])));
             }
             if(!defined('MP3_URL') && !empty($cli_options['media-url']))
             {
@@ -1768,13 +1769,13 @@ public static function bootstrap(array $SERVER, array $GET, array $argv)
             define('FORCE_PASSWORD', '');
 
         if(!defined('TMP_DIR')) {
-            define('TMP_DIR', DIR2CAST_BASE . '/temp');
+            define('TMP_DIR', DIR2CAST_BASE . 'temp');
         }
 
         if(!defined('MP3_BASE'))
         {
             if(!empty($SERVER['HTTP_HOST']))
-                define('MP3_BASE', dirname($SERVER['SCRIPT_FILENAME']));
+                define('MP3_BASE', slashdir(dirname($SERVER['SCRIPT_FILENAME'])));
             else
                 define('MP3_BASE', DIR2CAST_BASE);
         }
@@ -1783,14 +1784,14 @@ public static function bootstrap(array $SERVER, array $GET, array $argv)
         {
             if(!empty($GET['dir']))
             {
-                define('MP3_DIR', MP3_BASE . '/' . safe_path(magic_stripslashes($GET['dir'])));
+                define('MP3_DIR', slashdir(slashdir(MP3_BASE) . safe_path(magic_stripslashes($GET['dir']))));
                 if(!is_dir(MP3_DIR) or !is_readable(MP3_DIR))
                 {
                     ErrorHandler::display404($GET['dir']);
                 }
             }
             else
-                define('MP3_DIR', MP3_BASE);
+                define('MP3_DIR', slashdir(MP3_BASE));
         }
     }
     
@@ -1801,15 +1802,14 @@ public static function defaults(array $SERVER)
     {
         // if an MP3_DIR specific config file exists, load it now, as long as it's not the same file as the global one!
         if( 
-            file_exists( MP3_DIR . '/dir2cast.ini' ) and    
-            realpath(DIR2CAST_BASE . '/dir2cast.ini') != realpath( MP3_DIR . '/dir2cast.ini' ) 
+            file_exists( MP3_DIR . 'dir2cast.ini' ) and    
+            realpath(DIR2CAST_BASE . 'dir2cast.ini') != realpath( MP3_DIR . 'dir2cast.ini' ) 
         ) {
-            self::load_from_ini( MP3_DIR . '/dir2cast.ini' );
+            self::load_from_ini( MP3_DIR . 'dir2cast.ini' );
         }
         
         self::finalize();
         
-        
         if(!defined('MP3_URL'))
         {
             # This works on the principle that MP3_DIR must be under DOCUMENT_ROOT (otherwise how will you serve the MP3s?)
@@ -1818,9 +1818,9 @@ public static function defaults(array $SERVER)
             
             if(!empty($SERVER['HTTP_HOST']))
             {
-                $path_part = substr(MP3_DIR, strlen($SERVER['DOCUMENT_ROOT']));
+                $path_part = substr(slashdir(MP3_DIR), strlen(slashdir($SERVER['DOCUMENT_ROOT'])));
                 define('MP3_URL', 
-                    'http' . (!empty($SERVER['HTTPS']) ? 's' : '') . '://' . $SERVER['HTTP_HOST'] . '/' . ltrim( rtrim( $path_part, '/' ) . '/', '/' ));
+                    'http' . (!empty($SERVER['HTTPS']) ? 's' : '') . '://' . $SERVER['HTTP_HOST'] . '/' . ltrim( slashdir( $path_part ), '/' ));
             }
             else
                 define('MP3_URL', 'file://' . MP3_DIR );
@@ -1852,10 +1852,10 @@ public static function defaults(array $SERVER)
         
         if(!defined('DESCRIPTION'))
         {
-            if(file_exists(MP3_DIR . '/description.txt'))
-                define('DESCRIPTION', file_get_contents(MP3_DIR . '/description.txt'));
-            elseif(file_exists(DIR2CAST_BASE . '/description.txt'))
-                define('DESCRIPTION', file_get_contents(DIR2CAST_BASE . '/description.txt'));
+            if(file_exists(MP3_DIR . 'description.txt'))
+                define('DESCRIPTION', file_get_contents(MP3_DIR . 'description.txt'));
+            elseif(file_exists(DIR2CAST_BASE . 'description.txt'))
+                define('DESCRIPTION', file_get_contents(DIR2CAST_BASE . 'description.txt'));
             else
                 define('DESCRIPTION', 'Podcast');
         }
@@ -1877,20 +1877,20 @@ public static function defaults(array $SERVER)
             
         if(!defined('ITUNES_SUBTITLE'))
         {
-            if(file_exists(MP3_DIR . '/itunes_subtitle.txt'))
-                define('ITUNES_SUBTITLE', file_get_contents(MP3_DIR . '/itunes_subtitle.txt'));
-            elseif(file_exists(DIR2CAST_BASE . '/itunes_subtitle.txt'))
-                define('ITUNES_SUBTITLE', file_get_contents(DIR2CAST_BASE . '/itunes_subtitle.txt'));
+            if(file_exists(MP3_DIR . 'itunes_subtitle.txt'))
+                define('ITUNES_SUBTITLE', file_get_contents(MP3_DIR . 'itunes_subtitle.txt'));
+            elseif(file_exists(DIR2CAST_BASE . 'itunes_subtitle.txt'))
+                define('ITUNES_SUBTITLE', file_get_contents(DIR2CAST_BASE . 'itunes_subtitle.txt'));
             else
                 define('ITUNES_SUBTITLE', DESCRIPTION);
         }
         
         if(!defined('ITUNES_SUMMARY'))
         {
-            if(file_exists(MP3_DIR . '/itunes_summary.txt'))
-                define('ITUNES_SUMMARY', file_get_contents(MP3_DIR . '/itunes_summary.txt'));
-            elseif(file_exists(DIR2CAST_BASE . '/itunes_summary.txt'))
-                define('ITUNES_SUMMARY', file_get_contents(DIR2CAST_BASE . '/itunes_summary.txt'));
+            if(file_exists(MP3_DIR . 'itunes_summary.txt'))
+                define('ITUNES_SUMMARY', file_get_contents(MP3_DIR . 'itunes_summary.txt'));
+            elseif(file_exists(DIR2CAST_BASE . 'itunes_summary.txt'))
+                define('ITUNES_SUMMARY', file_get_contents(DIR2CAST_BASE . 'itunes_summary.txt'));
             else
                 define('ITUNES_SUMMARY', DESCRIPTION);
         }
@@ -1901,9 +1901,9 @@ public static function defaults(array $SERVER)
                 define('IMAGE', rtrim(MP3_URL, '/') . '/image.jpg');
             elseif(file_exists(rtrim(MP3_DIR, '/') . '/image.png'))
                 define('IMAGE', rtrim(MP3_URL, '/') . '/image.png');
-            elseif(file_exists(DIR2CAST_BASE . '/image.jpg'))
+            elseif(file_exists(DIR2CAST_BASE . 'image.jpg'))
                 define('IMAGE', rtrim(MP3_URL, '/') . '/image.jpg');
-            elseif(file_exists(DIR2CAST_BASE . '/image.png'))
+            elseif(file_exists(DIR2CAST_BASE . 'image.png'))
                 define('IMAGE', rtrim(MP3_URL, '/') . '/image.png');
             else
                 define('IMAGE', '');
@@ -1915,9 +1915,9 @@ public static function defaults(array $SERVER)
                 define('ITUNES_IMAGE', rtrim(MP3_URL, '/') . '/itunes_image.jpg');
             elseif(file_exists(rtrim(MP3_DIR, '/') . '/itunes_image.png'))
                 define('ITUNES_IMAGE', rtrim(MP3_URL, '/') . '/itunes_image.png');
-            elseif(file_exists(DIR2CAST_BASE . '/itunes_image.jpg'))
+            elseif(file_exists(DIR2CAST_BASE . 'itunes_image.jpg'))
                 define('ITUNES_IMAGE', rtrim(MP3_URL, '/') . '/itunes_image.jpg');
-            elseif(file_exists(DIR2CAST_BASE . '/itunes_image.png'))
+            elseif(file_exists(DIR2CAST_BASE . 'itunes_image.png'))
                 define('ITUNES_IMAGE', rtrim(MP3_URL, '/') . '/itunes_image.png');
             else
                 define('ITUNES_IMAGE', '');
@@ -1974,7 +1974,7 @@ public static function defaults(array $SERVER)
             define('CLOCK_OFFSET', 0);
 
         // Set up factory settings for Podcast subclasses
-        Dir_Podcast::$EMPTY_PODCAST_IS_ERROR = !defined('CLI_ONLY') || !CLI_ONLY;
+        Dir_Podcast::$EMPTY_PODCAST_IS_ERROR = !defined('CLI_ONLY');
         Dir_Podcast::$RECURSIVE_DIRECTORY_ITERATOR = RECURSIVE_DIRECTORY_ITERATOR;
         Dir_Podcast::$ITEM_COUNT = ITEM_COUNT;
         Dir_Podcast::$MIN_FILE_AGE = MIN_FILE_AGE;
@@ -2070,7 +2070,7 @@ public function update_mtime_if_metadata_files_modified()
             $filepath = rtrim(MP3_DIR, '/') . '/' . $file;
             if(!file_exists($filepath))
             {
-                $filepath = DIR2CAST_BASE . '/' . $file;
+                $filepath = DIR2CAST_BASE . $file;
             }
             if(!file_exists($filepath))
             {
@@ -2125,7 +2125,7 @@ public function output()
         if(!defined('OUTPUT_FILE'))
         {
             $output = $podcast->generate();
-            if(!defined('CLI_ONLY') || !CLI_ONLY)
+            if(!defined('CLI_ONLY'))
             {
                 $podcast->http_headers(strlen($output));
             }
@@ -2195,6 +2195,11 @@ function utf8_for_xml($s)
     return preg_replace('/[^\x{0009}\x{000a}\x{000d}\x{0020}-\x{D7FF}\x{E000}-\x{FFFD}]+/u', '', $s);
 }
 
+function slashdir($dir)
+{
+    return rtrim($dir, '/') . '/';
+}
+
 /* DISPATCH *********************************************/
 
 function main($args)
diff --git a/docker-compose/nginx/default.conf b/docker-compose/nginx/default.conf
index a918f54..f2ab099 100644
--- a/docker-compose/nginx/default.conf
+++ b/docker-compose/nginx/default.conf
@@ -8,7 +8,7 @@ server {
     # Don't allow downloading of dir2cast.ini, as it may contain sensitive
     # info such as the refresh password. Also, don't allow downloading of
     # dir2cast.php, for security and privacy reasons.
-    location ~ /dir2cast\.(ini|php)$ {
+    location ~ \.(ini|php)$ {
         return 404;
     }
 
diff --git a/test/FourOhFourTest.php b/test/FourOhFourTest.php
index 6b36221..3f2214d 100644
--- a/test/FourOhFourTest.php
+++ b/test/FourOhFourTest.php
@@ -11,8 +11,8 @@ public static function setUpBeforeClass(): void
 
     public function test_non_existent_dir_prints_bare_error_CLI_case(): void
     {
-        exec('php dir2cast.php --output=out.xml --media-dir=imaginary-dir', $output, $returncode);
-        $this->assertEquals("Not Found: imaginary-dir", implode("\n", $output));
+        exec('php dir2cast.php --media-dir=dir2cast.ini', $output, $returncode);
+        $this->assertEquals("Not Found: dir2cast.ini", implode("\n", $output));
         $this->assertEquals(254, $returncode);  // 254 is -2
     }
 
diff --git a/test/SettingsHandlerTest.php b/test/SettingsHandlerTest.php
index 51da4e1..401f1d1 100644
--- a/test/SettingsHandlerTest.php
+++ b/test/SettingsHandlerTest.php
@@ -137,7 +137,7 @@ public function test_default_defines_set()
         
         // should not be defined as $argv was empty
         $this->assertFalse(defined('CLI_ONLY'));
-        $this->assertEquals(DIR2CAST_BASE, realpath('..')); // from bootstrap.php
+        $this->assertEquals(DIR2CAST_BASE, slashdir(realpath('..'))); // from bootstrap.php
     }
 
     /**
@@ -172,7 +172,7 @@ public function test_defines_CLI_ONLY_if_argv0()
         $this->assertFalse(defined('CLI_ONLY'));
         SettingsHandler::bootstrap(array(), array(), array('dir2cast.php'));
         $this->assertTrue(defined('CLI_ONLY'));
-        $this->assertEquals(DIR2CAST_BASE, getcwd()); // from fake $argv
+        $this->assertEquals(DIR2CAST_BASE, slashdir(getcwd())); // from fake $argv
     }
 
     /**
@@ -187,7 +187,7 @@ public function test_bootstrap_sets_sensible_global_defaults_for_entire_installa
         SettingsHandler::bootstrap(array(), array(), array($argv0, $argv1));
         $this->assertEquals(MIN_CACHE_TIME, 5);
         $this->assertEquals(FORCE_PASSWORD, '');
-        $this->assertEquals(TMP_DIR, DIR2CAST_BASE . '/temp');
+        $this->assertEquals(TMP_DIR, DIR2CAST_BASE . 'temp');
         $this->assertEquals(MP3_BASE, DIR2CAST_BASE);
         $this->assertEquals(MP3_DIR, DIR2CAST_BASE);
     }
@@ -207,8 +207,8 @@ public function test_when_SERVER_HTTP_HOST_then_MP3_BASE_defaults_to_same_dir()
             /* $GET */ array(),
             /* $argv */ array()
         );
-        $this->assertEquals(MP3_BASE, '/var/www');
-        $this->assertEquals(MP3_DIR, '/var/www');
+        $this->assertEquals(MP3_BASE, '/var/www/');
+        $this->assertEquals(MP3_DIR, '/var/www/');
     }
     
     /**
@@ -322,8 +322,8 @@ public function test_cli_media_dir_a_ok()
         mkdir($this->temp_file);
 
         SettingsHandler::bootstrap(array(), array(), array("dir2cast.php", "--media-dir={$this->temp_file}"));
-        $this->assertEquals(MP3_BASE, realpath('.'));
-        $this->assertEquals(MP3_DIR, realpath($this->temp_file));
+        $this->assertEquals(MP3_BASE, slashdir(realpath('.')));
+        $this->assertEquals(MP3_DIR, slashdir(realpath($this->temp_file)));
         $this->assertFalse(http_response_code());
     }
 
@@ -338,8 +338,8 @@ public function test_GET_media_dir_a_ok()
         mkdir('../' . $this->temp_file);
 
         SettingsHandler::bootstrap(array(), array("dir" => $this->temp_file), array());
-        $this->assertEquals(MP3_BASE, realpath('..'));  // due to bootstrap.php chdir
-        $this->assertEquals(MP3_DIR, realpath('../' . $this->temp_file));
+        $this->assertEquals(MP3_BASE, slashdir(realpath('..')));  // due to bootstrap.php chdir
+        $this->assertEquals(MP3_DIR, slashdir(realpath('../' . $this->temp_file)));
         $this->assertFalse(http_response_code());
     }
 
@@ -355,8 +355,8 @@ public function test_GET_media_dir_safe_dot_dot_1()
         chdir('deep/root');
         SettingsHandler::bootstrap(array(), array("dir" => ".."), array());
 
-        $this->assertEquals(MP3_BASE, realpath("{$this->starting_dir}/.."));  // due to bootstrap.php chdir
-        $this->assertEquals(slashdir(MP3_DIR), slashdir(MP3_BASE));
+        $this->assertEquals(MP3_BASE, slashdir(realpath("{$this->starting_dir}/..")));  // due to bootstrap.php chdir
+        $this->assertEquals(MP3_DIR, slashdir(MP3_BASE));
         $this->assertFalse(http_response_code());
     }
     
@@ -372,8 +372,8 @@ public function test_GET_media_dir_safe_dot_dot_2()
         chdir('deep/root');
         SettingsHandler::bootstrap(array(), array("dir" => "../../.."), array());
 
-        $this->assertEquals(MP3_BASE, realpath("{$this->starting_dir}/.."));  // due to bootstrap.php chdir
-        $this->assertEquals(slashdir(MP3_DIR), slashdir(MP3_BASE));
+        $this->assertEquals(MP3_BASE, slashdir(realpath("{$this->starting_dir}/..")));  // due to bootstrap.php chdir
+        $this->assertEquals(MP3_DIR, slashdir(MP3_BASE));
         $this->assertFalse(http_response_code());
     }
 
@@ -425,7 +425,7 @@ public function test_GET_media_dir_safe_dir_with_good_base()
         SettingsHandler::bootstrap(array(), array("dir" => "root"), array());
 
         $this->assertEquals(MP3_BASE, realpath(".."));
-        $this->assertEquals(MP3_DIR, realpath('.'));
+        $this->assertEquals(MP3_DIR, realpath('.') . '/');
         $this->assertFalse(http_response_code());
     }
 
@@ -528,7 +528,7 @@ public function test_CLI_ONLY_sensible_defaults()
         SettingsHandler::bootstrap(array(), array(), array('dir2cast.php'));
         SettingsHandler::defaults(array());
         
-        $this->assertEquals(MP3_URL, 'file://' . getcwd());
+        $this->assertEquals(MP3_URL, 'file://' . getcwd() . '/');
         $this->assertEquals(LINK, 'http://www.example.com/');
         $this->assertEquals(RSS_LINK, 'http://www.example.com/rss');
         $this->assertEquals(TITLE, 'test'); // name of this folder
diff --git a/test/bootstrap.php b/test/bootstrap.php
index c2a1b9b..9fe6f3e 100644
--- a/test/bootstrap.php
+++ b/test/bootstrap.php
@@ -124,11 +124,6 @@ function fake_getopt($argv_in, $short_options, $long_options)
     return array();
 }
 
-function slashdir($dir)
-{
-    return rtrim($dir, '/') . '/';
-}
-
 define('NO_DISPATCHER', true);
 
 require_once('../dir2cast.php');