do you want to know how to disable register_global in your linux apache server? if so you can follow these commands which cover disabling the register_global settings in your php.ini file

first step is to find your php.ini file. if you have a fedora/redhat/centos server you find it at /etc/php.ini so you can send this command

# nano /etc/php.ini

look for this line:
register_globals = Off

change it to
register_globals = On

save the changes and now restart your apache server
# /etc/init.d/httpd restart

there is an alternative if you dont have access to the shell to edit the /etc/php.ini file

you can put this code in your php file to disable

to disable
ini_set('register_globals', false)

to enable
ini_set('register_globals', true)