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MYSQL-NOBLOCK(1)					      MYSQL-NOBLOCK(1)



NAME
       query_runner_init,  query_runner_execute, query_runner_get_response_fd,
       query_runner_get_request_fd,	      query_runner_handle_all_results,
       query_runner_handle_next_result, query_runner_shutdown,

SYNOPSIS
       #include "mysql-noblock.h"

       #define RUNNER_RESULT_EAGAIN -1
       #define RUNNER_RESULT_SQL_ERROR 0
       #define RUNNER_RESULT_ROWS 1
       #define RUNNER_RESULT_NONE 2

       query_runner *query_runner_init(char *hostname, char *user,
				       char *password, char *database);

       void query_runner_execute(query_runner *runner, char *query,
				 query_runner_callback callback,
				 void *callback_data );

       int query_runner_get_response_fd(query_runner *runner);

       int query_runner_get_request_fd(query_runner *runner);

       void query_runner_shutdown(query_runner * runner);

       int query_runner_handle_next_result(query_runner *runner);

       void query_runner_handle_all_results(query_runner *runner);

       typedef void (*query_runner_callback)(int, MYSQL_RES *, void *);


DESCRIPTION
       A  simple library for integrating MySQL into non-blocking, event-driven
       applications. All queries are submitted to a separate thread which sig‐
       nals  query completion by writing to a UNIX pipe. You can find out when
       the result is ready by using the file descriptor of the	pipe  in  your
       own event loops using select(), poll(), etc.


USAGE
       First write a callback for your query:

	void sql_results_callback(int result_code,
				  MYSQL_RES *res,
				  void *user_data) {
	    if (result_code == RUNNER_RESULT_SQL_ERROR) {
		print("Query Failed!");
		return;
	    }
	    /* Now do something with res (see mysql manual) */
	}

       Next you will need to start the runner somewhere in your program:

	query_runner_init("myhost","username","password","database");

       To integrate into your I/O event loop, you will need the runner's fd:

	int runner_response_fd = query_runner_get_response_fd();

       To submit queries, use query_runner_execute():

	query_runner_execute(runner,
			     "SELECT foo FROM bar",
			     sql_results_callback,
			     my_data);

       When  the  query  is complete, runner_response_fd will become ready for
       reading.  DO NOT read directly from the fd, but instead use  query_run‐
       ner_handle_all_results() or query_runner_handle_next_result(). If there
       are no results ready these functions will do nothing.






				 23 January 10		      MYSQL-NOBLOCK(1)