php man page for mysql_ping

MYSQL_PING(3)								 1							     MYSQL_PING(3)

mysql_ping - Ping a server connection or reconnect if there is no connection

SYNOPSIS
       Warning

	      This  extension  is deprecated as of PHP 5.5.0, and will be removed in the future. Instead, the MySQLi or PDO_MySQL extension should
	      be used. See also MySQL: choosing an API guide and related FAQ for more information. Alternatives to this function include:

		     omysqli_ping(3)

       bool mysql_ping ([resource  $link_identifier = NULL])

DESCRIPTION
	Checks whether or not the connection to the server is working. If it has gone down, an automatic reconnection is attempted. This  function
       can  be	used  by  scripts that remain idle for a long while, to check whether or not the server has closed the connection and reconnect if
       necessary.

       Note

	       Automatic reconnection is disabled by default in versions of MySQL >= 5.0.3.

	      o $
		link_identifier -The MySQL connection. If the link identifier is not specified,  the  last  link  opened  by  mysql_connect(3)	is
		assumed. If no such link is found, it will try to create one as if mysql_connect(3) was called with no arguments. If no connection
		is found or established, an E_WARNING level error is generated.

	Returns TRUE if the connection to the server MySQL server is working, otherwise FALSE.

       Example #1

	      A mysql_ping(3) example

	      <?php
	      set_time_limit(0);

	      $conn = mysql_connect('localhost', 'mysqluser', 'mypass');
	      $db   = mysql_select_db('mydb');

	      /* Assuming this query will take a long time */
	      $result = mysql_query($sql);
	      if (!$result) {
		  echo 'Query #1 failed, exiting.';
		  exit;
	      }

	      /* Make sure the connection is still alive, if not, try to reconnect */
	      if (!mysql_ping($conn)) {
		  echo 'Lost connection, exiting after query #1';
		  exit;
	      }
	      mysql_free_result($result);

	      /* So the connection is still alive, let's run another query */
	      $result2 = mysql_query($sql2);
	      ?>

       mysql_thread_id(3), mysql_list_processes(3).

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