So what server softare are you using? Apache, Nginx etc
Here's examples on Apache, as it's normally what people use.
Code:
<IfModule mod_rewrite.c>
RewriteEngine on
RewriteBase /onyx/
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ /onyx/index.php/$1 [L,QSA]
</IfModule>
Code:
<IfModule mod_rewrite.c>
RewriteEngine on
RewriteBase /onyx/
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php/$1 [L,QSA]
</IfModule>