Timer Functions

Functions
WB_UINT64	WBGetTimeIndex (void)
	Returns the current 'time index' (in microseconds) More...
int	CreateTimer (Display *pDisplay, Window wID, unsigned long lInterval, long lID, int iPeriodic)
	Creates a one-shot or periodic timer. More...
void	DeleteTimer (Display *pDisplay, Window wID, long lID)
	Deletes an existing timer's resources. More...

Detailed Description

The X11workbench Toolkit API has support for one-shot and periodic timer events that are generated via XClientEvent using aWM_TIMER.
These timer events are NOT hyper-accurate, although the timer event time is expressed in microseconds (for math efficiency and convenience). The message loop will check for 'crossing an event time' and generate events whenever a limit has been crossed. This means that event processing time can easily affect timer accuracy. Additionally, if a timer's period is less than the processing time of an event, a timer may be 'missed' as a a result. For this reason you should use a worker thread for timing that requires precise accuracy.

Function Documentation

int CreateTimer	(	Display *	pDisplay,
		Window	wID,
		unsigned long	lInterval,
		long	lID,
		int	iPeriodic
	)

Creates a one-shot or periodic timer.

Parameters

pDisplay	The display associated with the specified window
wID	The window that receives the aWM_TIMER XClientEvent (None == application)
lInterval	The timer interval in microseconds
lID	The unique timer identifier
iPeriodic	Non-zero for a recurring timer, zero for a 'one-shot' timer.

Returns

Non-zero on error, zero on success.

Timers can either be periodic (recurring), or one-shot. Use this function to create them. A timer created by this function must be subsequently deleted via DeleteTimer()

Header File: window_helper.h

Definition at line 3384 of file window_helper.c.

void DeleteTimer	(	Display *	pDisplay,
		Window	wID,
		long	lID
	)

Deletes an existing timer's resources.

Parameters

pDisplay	The display associated with the specified window
wID	The window associated with the timer
lID	The unique ID associated with the timer

Timers created via CreateTimer() must be subsequently deleted using this function by passing the same Display, Window, and Timer 'unique' ID that were used to create it.

Header File: window_helper.h

Definition at line 3481 of file window_helper.c.

WB_UINT64 WBGetTimeIndex

(

void

)

Returns the current 'time index' (in microseconds)

Returns

An unsigned 64-bit time index value, in microseconds

The 'time index' is the master timer that determines when a timer event will be generated. By design it uses a 64-bit integer that never 'wraps around' to zero. It is generally derived from the 'gettimeofday' API call for operating systems such as BSD and Linux that support the POSIX standard.

Header File: window_helper.h

Definition at line 3365 of file window_helper.c.