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_ftime_s, _ftime32_s, _ftime64_s

  • Άρθρο

Gets the current time. These functions are versions of _ftime, _ftime32, _ftime64 with security enhancements as described in Security features in the CRT.

Syntax

errno_t _ftime_s( struct _timeb *timeptr );
errno_t _ftime32_s( struct __timeb32 *timeptr );
errno_t _ftime64_s( struct __timeb64 *timeptr );

Parameters

timeptr
Pointer to a _timeb, __timeb32, or __timeb64 structure.

Return value

Zero if successful, an error code on failure. If timeptr is NULL, the return value is EINVAL.

Remarks

The _ftime_s function gets the current local time and stores it in the structure pointed to by timeptr. The _timeb, __timeb32, and __timeb64 structures are defined in SYS\Timeb.h. They contain four fields, which are listed in the following table.

Field Description
dstflag Nonzero if daylight savings time is currently in effect for the local time zone. (See _tzset for an explanation of how daylight savings time is determined.)
millitm Fraction of a second in milliseconds.
time Time in seconds since midnight (00:00:00), January 1, 1970, coordinated universal time (UTC).
timezone Difference in minutes, moving westward, between UTC and local time. The value of timezone is set from the value of the global variable _timezone (see _tzset).

The _ftime64_s function, which uses the __timeb64 structure, allows file-creation dates to be expressed up through 23:59:59, December 31, 3000, UTC; whereas _ftime32_s only represents dates through 23:59:59 January 18, 2038, UTC. Midnight, January 1, 1970, is the lower bound of the date range for all these functions.

The _ftime_s function is equivalent to _ftime64_s, and _timeb contains a 64-bit time, unless _USE_32BIT_TIME_T is defined, in which case the old behavior is in effect; _ftime_s uses a 32-bit time and _timeb contains a 32-bit time.

_ftime_s validates its parameters. If passed a null pointer as timeptr, the function invokes the invalid parameter handler, as described in Parameter validation. If execution is allowed to continue, the function sets errno to EINVAL.

By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.

Requirements

Function Required header
_ftime_s <sys/types.h> and <sys/timeb.h>
_ftime32_s <sys/types.h> and <sys/timeb.h>
_ftime64_s <sys/types.h> and <sys/timeb.h>

For more compatibility information, see Compatibility.

Libraries

All versions of the C run-time libraries.

Example

// crt_ftime64_s.c
// This program uses _ftime64_s to obtain the current
// time and then stores this time in timebuffer.

#include <stdio.h>
#include <sys/timeb.h>
#include <time.h>

int main( void )
{
   struct _timeb timebuffer;
   char timeline[26];
   errno_t err;
   time_t time1;
   unsigned short millitm1;
   short timezone1;
   short dstflag1;

   _ftime64_s( &timebuffer );

    time1 = timebuffer.time;
    millitm1 = timebuffer.millitm;
    timezone1 = timebuffer.timezone;
    dstflag1 = timebuffer.dstflag;

   printf( "Seconds since midnight, January 1, 1970 (UTC): %I64d\n",
   time1);
   printf( "Milliseconds: %d\n", millitm1);
   printf( "Minutes between UTC and local time: %d\n", timezone1);
   printf( "Daylight savings time flag (1 means Daylight time is in "
           "effect): %d\n", dstflag1);

   err = ctime_s( timeline, 26, & ( timebuffer.time ) );
   if (err)
   {
       printf("Invalid argument to ctime_s. ");
   }
   printf( "The time is %.19s.%hu %s", timeline, timebuffer.millitm,
           &timeline[20] );
}

Seconds since midnight, January 1, 1970 (UTC): 1051553334
Milliseconds: 230
Minutes between UTC and local time: 480
Daylight savings time flag (1 means Daylight time is in effect): 1
The time is Mon Apr 28 11:08:54.230 2003

See also

Time management
asctime, _wasctime
ctime, _ctime32, _ctime64, _wctime, _wctime32, _wctime64
gmtime, _gmtime32, _gmtime64
localtime, _localtime32, _localtime64
time, _time32, _time64