include/sys/time.h File Reference

#include <event.h>

Data Structures
struct	timeval
struct	itimerval
Defines
#define	_TIME_H   1
Typedefs
typedef struct timeval	timeval_t
typedef struct itimerval	itimerval_t
Functions
int16_t	gettimeofday (struct timeval *tv)
int16_t	settimeofday (const struct timeval *tv)
int16_t	timer ()
int16_t	gettitimer (int16_t timerid, itimerval_t *value)
int16_t	setitimer (int16_t timerid, const itimerval_t *value, itimerval_t *old_value, void(*timer_handler)(event_t event, void *cbargs, void *context), void *resource, void *context)

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Define Documentation

#define _TIME_H   1

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Typedef Documentation

typedef struct itimerval itimerval_t

typedef struct timeval timeval_t

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Function Documentation

int16_t gettimeofday

(

struct timeval *

tv

)

A system call to access time of day.

Precondition:

Do not call this inside the interrupt handler context.

Postcondition:

If successful, tv contains the system's time of day.

Parameters:

[out]

tv

system fills the time value structure with system's time of the day.

Returns:

0 if succeed or -1 if fail and errno is set appropriately.

Errors:

ENOTTIMESYNC suggests the returned time value is not synchronized.

int16_t gettitimer	(	int16_t	timerid,
		itimerval_t *	value
	)

Get value of an interval timer.

Parameters:

[in]	timerid	a valid timer id return by timer()
[out]	value	to get the value of the timer

Returns:

0 if succeed or -1 if fail and errno is set appropriately.

Errors:

EINVAL if invalid parameters are passed

int16_t setitimer	(	int16_t	timerid,
		const itimerval_t *	value,
		itimerval_t *	old_value,
		void(*)(event_t event, void *cbargs, void *context)	timer_handler,
		void *	resource,
		void *	context
	)

Set the value of an interval timer. Setting the value to zero means stopping the current timer.

Parameters:

[in]	timerid	a valid timer id return by timer().
[in]	value	new interval timer value
[out]	old_value	if old timer interval is not zero, it will copied into old_value. Pass NULL if don't care.
[in]	timer_handler	the continuation callback handler that will be fired when value becomes zero. If NULL is passed here, the call will fail.
[in]	resource	no requirement here.
[in]	context	user context

Returns:

0 if succeed or -1 if fail and errno is set appropriately.

Errors:

EBUSY if the resource with timerid is busy

EINVAL if invalid parameters are passed

Callback Descriptions

timer_handler

Parameters:

[in]	event	Type is SETITIMER in EventsEnum.
[in]	cbargs	return resource in setitimer().
[in]	context	return context in setitimer().

Returns:

None.

int16_t settimeofday

(

const struct timeval *

tv

)

A system call to set system's time of day.

Precondition:

Do not call this inside the interrupt handler context.

Postcondition:

If successful, system's time of day will be set to that specified in tv.

Parameters:

[in]

tv

the time value structure that the system will take as time of day.

Returns:

0 if succeed or -1 if fail and errno is set appropriately.

Errors:

EINVAL invalid argument

int16_t timer

(

)

Request a unique resource identifier that enables scheduling timers.

Returns:

a non-zero resource identifiier if succeed or -1 if fail and errno is set appropriately.

Errors:

ENFILE all unique resource identifier has been used up