PUBLIC: event interface functions

handle different aspects of the MqS event-queue More...

Typedefs
typedef void(*	MqEventF )(struct MqS *const )
	prototype for a Event-Checking function
Enumerations
enum	MqWaitOnEventE { MQ_WAIT_NO = 0, MQ_WAIT_ONCE = 1, MQ_WAIT_FOREVER = 2 }
	wait for an event? More...
Functions
MQ_EXTERN enum MqErrorE	MqProcessEvent (struct MqS *const context, MQ_TIME_T timeout, enum MqWaitOnEventE const wait)
	Waiting for an incoming packet on all open msgque objects.
Variables
enum MqErrorE(*	EventCreateF )(struct MqS *const )
	prototype for a Event-Check function

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Detailed Description

handle different aspects of the MqS event-queue

the event-queue have to be linked into an existing event-processing infrastructure. the linking is done by defining prototypes for two independent functions:

• MqEventF is used to call an external event processing function (e.g. Tcl_DoOneEvent)
• EventCreateF is used to add events, created by the file-handles owned by the MqS objects, into the external event-queue (e.g. Tcl_QueueEvent)

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Typedef Documentation

typedef void( * MqEventF)(struct MqS *const )

prototype for a Event-Checking function

Definition at line 439 of file msgque.h.

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Enumeration Type Documentation

enum MqWaitOnEventE

wait for an event?

Enumerator:

MQ_WAIT_NO	just do the check
MQ_WAIT_ONCE	wait for one new event
MQ_WAIT_FOREVER	wait forever

Definition at line 300 of file msgque.h.

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Function Documentation

MQ_EXTERN enum MqErrorE MqProcessEvent	(	struct MqS *const	context,
		MQ_TIME_T	timeout,
		enum MqWaitOnEventE const	wait
	)

Waiting for an incoming packet on all open msgque objects.

This function is used to wait for (e.g. MQ_WAIT_ONCE) or check (e.g. MQ_WAIT_NO) for an incoming event. If an event occurs the header of the Msgque packet is parsed and the according service-handle is called. if MQ_WAIT_FOREVER is set the function will never return, accept for an error or on exit. This function is usually used on a server to enter the event-loop and wait for incoming service requests.

Parameters:

[in]	context	the initial MqS object created by MqContextCreate
	timeout	time_t type value for timeout in seconds. A value of -1 is used as default using MQ_TIMEOUT seconds.
	wait	should the code wait forever (e.g. MQ_WAIT_FOREVER), just wait for the next event (e.g. MQ_WAIT_ONCE) or just return after one single test (MQ_WAIT_NO)"

Returns:

the MqErrorE return status MQ_OK, MQ_ERROR or MQ_CONTINUE

Attention:

The timeout argument is only used if MQ_WAIT_ONCE is set.

A typical server looks like:

...
MqErrorCheck(MqLinkCreate(ctx,argv,alfa);
...
MqErrorCheck(MqProcessEvent(ctx, MQ_TIMEOUT, MQ_WAIT_FOREVER);
...
MqLinkDelete(ctx);
...

Definition at line 1062 of file msgque.c.

References MqLinkS::io, MqS::link, MQ_CONTINUE, MQ_ERROR, MQ_EXIT, MQ_OK, MQ_SELECT_RECV, MQ_TIMEOUT, MQ_TIMEOUT_USER, mq_timeval, MQ_WAIT_FOREVER, MQ_WAIT_ONCE, MqDLogC, MqDLogCL, MqDLogVL, MqErrorCheck, MqErrorStack, MqLogErrorCode(), MqSendEND(), MqSendSTART(), MqSetDebugLevel, pIoGetTimeout(), pIoSelectStart(), pWaitOnEvent(), and sMqEventStart().

Referenced by MqSendEND_AND_WAIT(), pWaitForToken(), sSysServerThreadCreate(), and SysServerFork().

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Variable Documentation

enum MqErrorE( * EventCreateF)(struct MqS *const )

prototype for a Event-Check function

This function is called by the libmsgque_private event-loop as idle-task in MqProcessEvent