PHP 5, PHP 7 < 7.4.0
ibase_close - Close a connection to an InterBase database
ibase_close( [resource$connection_id = null] ): bool
Closes the link to an InterBase database that's associated with a connection id returned from ibase_connect. Default transaction on link is committed, other transactions are rolled back.
An InterBase link identifier returned from ibase_connect. If omitted, the last opened link is assumed.
Returns true on success or false on failure.