PHP - Where should I call ini_set?

I am looking for a best practice for where I should place the statement ini_set.

For example,

ini_set('session.use_开发者_C百科only_cookies', 1);

Thank you

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I normally place them all in my index.php file as early as is practical. Normally, immediately after defining constants for the root directory of my application and before anything could go wrong (for example before any requires)