php - Codeigniter bad system folder path -

i've installed codeigniter /usr/share/pear/codeigniter. if set in app's index.php

$system_path = '/usr/share/pear/codeigniter/system'; 

it works well.

but when mount --bind or copy /pub/codeigniter, , set $system_path /pub/codeigniter/system, doesn't work , ci displays error message:

your system folder path not appear set correctly. please open following file , correct this: index.php 

the permissions:

$ ls -ld /usr/share/pear/codeigniter/{,*} drwxr-xr-x  4 root root 4096 febr  17 13.07 /usr/share/pear/codeigniter/ drwxr-xr-x 15 root root 4096 febr  17 13.07 /usr/share/pear/codeigniter/application -rw-r--r--  1 root root 6357 febr  17 13.07 /usr/share/pear/codeigniter/index.php drwxr-xr-x  8 root root 4096 febr  17 13.07 /usr/share/pear/codeigniter/system  $ ls -ld /pub/codeigniter/{,*} drwxr-xr-x  4 root root 4096 júl   15 13.20 /pub/codeigniter/ drwxr-xr-x 15 root root 4096 febr  17 13.07 /pub/codeigniter/application -rw-r--r--  1 root root 6357 febr  17 13.07 /pub/codeigniter/index.php drwxr-xr-x  8 root root 4096 júl   15 13.20 /pub/codeigniter/system 

i think php's is_dir function fails don't know why.

any suggestion?

my fault: in /etc/php/php.ini should add /pub open_basedir's list, restart webserver , fine.