Failed Opening required error. required once - php

Question

I am getting the following error from my website in the error logs:
[Wed Jul 02 07:13:58 2014] [error] [client **.**.**.**]
PHP Fatal error: require_once(): Failed opening required '/var/zpanel/hostdata/
zadmin/core/public_html/loader.php' (include_path='.:/usr/share/pear:/usr/share/php')
in /var/zpanel/hostdata/zadmin/public_html/cmcatering_co_uk/index.php on line 3
In index.php I have the following:
<?php
$code_base = "/var/zpanel/hostdata/zadmin/core";
require_once($code_base . "/public_html/loader.php");
?>
The loader.php file is in the correct place and so I am a bit confused as to why this is happening. I tried putting the core folder in /usr/share/php but this did not fix the problem. Any suggestions?
edit:
I have also just seen this error:
[Wed Jul 02 07:36:58 2014] [error] [client 94.10.110.115] PHP Warning: require_once(/usr/share/php/core/public_html/loader.php): failed to open stream: Operation not permitted in /var/zpanel/hostdata/zadmin/public_html/cmcatering_co_uk/index.php on line 3
httpd.conf:
# ZPanel Apache Include file for CentOS Linux
# Written by Bobby Allen, 15/05/2011
# Set the Zpanel Alias (used for development, sable will eventually use a VHOST)
Alias /zpanel /etc/zpanel/panel
# Setup the directory settings and PHP security flags for the Zpanel application directory.
<Directory /etc/zpanel/panel>
Options FollowSymLinks
AllowOverride All
DirectoryIndex index.php
<IfModule mod_php5.c>
AddType application/x-httpd-php .php
php_flag magic_quotes_gpc Off
php_flag track_vars On
php_flag register_globals Off
php_admin_value upload_tmp_dir /etc/zpanel/temp
</IfModule>
</Directory>
# Disallow web access to directories that don't need it/that we don't want people looking in!
<Directory /etc/zpanel/panel/cnf>
Order Deny,Allow
Deny from All
</Directory>
# Set server tokens (security??)
ServerTokens Maj
# Now we include the generic VHOST configuration file that holds all the ZPanel user hosted vhost data
Include /etc/zpanel/configs/apache/httpd-vhosts.conf

Answer 1

if you read the error message then you well see:
Operation not permitted
Your webserver process has no permissions to access
/usr/share/php/core/public_html/
In many cases webservers are bound to their root.
/var/zpanel/hostdata/

Answer 2

It looks as though this is a permissions issue due to the operation not permitted error. Look at whether your server is giving php access to the given folder in its configuration. Also just for a sanity check, echo out the filename as it is passed to your require_once.
Would be helpful if you posted your apache site config.

Answer 3

<?php
$code_base = "/var/zpanel/hostdata/zadmin/core";
require_once("<?php echo $code_base; ?>/public_html/loader.php");
?>