Function: Deletes a file.

Function: Tests if the supplied date is valid for the Gregorian calendar.

Function: Loads the auth check for monitoring whether the user is still logged in.

Function: Outputs the HTML that shows the wp-login dialog when the user is no longer logged in.

Function: Retrieves IDs that are not already present in the cache.

Function: Tests if the current device has the capability to upload files.

Function: Tests if a given path is a stream URL

Function: Sends a HTTP header to disable content type sniffing in browsers which support it.