(PHP 4, PHP <=5.2.0)
ifx_close — Close Informix connection
ifx_close() closes the link to an Informix database that's associated with the specified link identifier.
Note that this isn't usually necessary, as non-persistent open links are automatically closed at the end of the script's execution.
ifx_close() will not close persistent links generated by ifx_pconnect().
The link identifier. If not specified, the last opened link is assumed.
成功时返回 TRUE， 或者在失败时返回 FALSE.
Example #1 Closing a Informix connection
<?php
$conn_id = ifx_connect ("mydb@ol_srv", "itsme", "mypassword");
/* ... some queries and stuff ... */
ifx_close($conn_id);
?>