Simple instructions on how to open vi editor to edit the php.ini file.
Type:
cd /etc
ls
Check that there is the php.ini listed if not you will have to ask your hosting provider where it is.
vi php.ini
Find the bit in php.ini you would like to edit.
i
- This enables you to edit the php.ini file
After changing the file, please Esc.
:wq
- (w = saves the file, q = quit)
reboot your server and your done.