Retrieves the current thread ID. If the connection is lost, and a reconnect with mysql_ping() is executed, the thread ID will change. This means only retrieve the thread ID when needed.
The MySQL connection. If the
link identifier is not specified, the last link opened by
mysql_connect() is assumed. If no such link is found, it
will try to create one as if mysql_connect() was called
with no arguments. If by chance no connection is found or established, an
E_WARNING level warning is generated.
$link = mysql_connect('localhost', 'mysql_user', 'mysql_password');
$thread_id = mysql_thread_id($link);
printf("current thread id is %d\n", $thread_id);
The above example will output something similar to:
current thread id is 73