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time.ch

Declarations

Public Only
Publicfunction difftime
func difftime(time_end : time_t, time_beg : time_t) : double
Computes difference between two calendar times as time_t objects (time_end - time_beg) in seconds. If time_end refers to time point before time_beg then the result is negative.

Parameters

  • time_beg, time_end - times to compare @return Difference between two times in seconds. @see Difference between two times in seconds.

Returns

Difference between two times in seconds. @see Difference between two times in seconds.

See Also

  • Difference between two times in seconds.
Publicfunction time
func time(arg : *time_t) : time_t
Returns the current calendar time encoded as a time_t object, and also stores it in the time_t object pointed to by arg (unless arg is a null pointer)

Parameters

  • arg - pointer to a time_t object where the time will be stored, or a null pointer @return Current calendar time encoded as time_t object on success, (time_t)(-1) on error. If arg is not a null pointer, the return value is also stored in the object pointed to by arg. @see https:en.cppreference.com/w/c/chrono/time

Returns

Current calendar time encoded as time_t object on success, (time_t)(-1) on error. If arg is not a null pointer, the return value is also stored in the object pointed to by arg. @see https:en.cppreference.com/w/c/chrono/time

See Also

  • https:en.cppreference.com/w/c/chrono/time
Publicfunction clock
func clock() : clock_t
Returns the approximate processor time used by the process since the beginning of an implementation-defined era related to the program's execution. To convert result value to seconds, divide it by CLOCKS_PER_SEC. Only the difference between two values returned by different calls to clock is meaningful, as the beginning of the clock era does not have to coincide with the start of the program. clock time may advance faster or slower than the wall clock, depending on the execution resources given to the program by the operating system. For example, if the CPU is shared by other processes, clock time may advance slower than wall clock. On the other hand, if the current process is multithreaded and more than one execution core is available, clock time may advance faster than wall clock.

Returns

Processor time used by the program so far or (clock_t)(-1) if that information is unavailable or its value cannot be represented. @see https:en.cppreference.com/w/c/chrono/clock

See Also

  • https:en.cppreference.com/w/c/chrono/clock
Publicfunction timespec_get
func timespec_get(ts : *timespec, base : int) : int
Modifies the timespec object pointed to by ts to hold the current calendar time in the time base base. Other macro constants beginning with TIME_ may be provided by the implementation to indicate additional time bases If base is TIME_UTC, then ts->tv_sec is set to the number of seconds since an implementation defined epoch, truncated to a whole value ts->tv_nsec member is set to the integral number of nanoseconds, rounded to the resolution of the system clock

Parameters

  • ts - pointer to an object of type struct timespec @param base - TIME_UTC or another nonzero integer value indicating the time base @return The value of base if successful, zero otherwise. @see https:en.cppreference.com/w/c/chrono/timespec_get
  • base - TIME_UTC or another nonzero integer value indicating the time base @return The value of base if successful, zero otherwise. @see https:en.cppreference.com/w/c/chrono/timespec_get

Returns

The value of base if successful, zero otherwise. @see https:en.cppreference.com/w/c/chrono/timespec_get

See Also

  • https:en.cppreference.com/w/c/chrono/timespec_get
Publicfunction timespec_getres
func timespec_getres(ts : *timespec, base : int) : int
If ts is non-null and base is supported by timespec_get, modifies *ts to hold the resolution of time provided by timespec_get for base. For each supported base, multiple calls to timespec_getres during the same program execution have identical results.

Parameters

  • ts - pointer to an object of type struct timespec @param base - TIME_UTC or another nonzero integer value indicating the time base @return The value of base if base is supported, zero otherwise. @see https:en.cppreference.com/w/c/chrono/timespec_getres
  • base - TIME_UTC or another nonzero integer value indicating the time base @return The value of base if base is supported, zero otherwise. @see https:en.cppreference.com/w/c/chrono/timespec_getres

Returns

The value of base if base is supported, zero otherwise. @see https:en.cppreference.com/w/c/chrono/timespec_getres

See Also

  • https:en.cppreference.com/w/c/chrono/timespec_getres
Publicfunction strftime
func strftime(str : *char, count : size_t, format : *char, tp : *tm) : size_t
Converts the date and time information from a given calendar time tp to a null-terminated multibyte character string str according to format string format. Up to count bytes are written.

Parameters

  • str - pointer to the first element of the char array for output @param count - maximum number of bytes to write @param format - pointer to a null-terminated multibyte character string specifying the format of conversion @param tp - pointer to a struct tm object specifying the time to format @return The number of bytes written into the character array pointed to by str not including the terminating '\0' on success. If count was reached before the entire string could be stored, ​0​ is returned and the contents are indeterminate. @see https:en.cppreference.com/w/c/chrono/strftime
  • count - maximum number of bytes to write @param format - pointer to a null-terminated multibyte character string specifying the format of conversion @param tp - pointer to a struct tm object specifying the time to format @return The number of bytes written into the character array pointed to by str not including the terminating '\0' on success. If count was reached before the entire string could be stored, ​0​ is returned and the contents are indeterminate. @see https:en.cppreference.com/w/c/chrono/strftime
  • format - pointer to a null-terminated multibyte character string specifying the format of conversion @param tp - pointer to a struct tm object specifying the time to format @return The number of bytes written into the character array pointed to by str not including the terminating '\0' on success. If count was reached before the entire string could be stored, ​0​ is returned and the contents are indeterminate. @see https:en.cppreference.com/w/c/chrono/strftime
  • tp - pointer to a struct tm object specifying the time to format @return The number of bytes written into the character array pointed to by str not including the terminating '\0' on success. If count was reached before the entire string could be stored, ​0​ is returned and the contents are indeterminate. @see https:en.cppreference.com/w/c/chrono/strftime

Returns

The number of bytes written into the character array pointed to by str not including the terminating '\0' on success. If count was reached before the entire string could be stored, ​0​ is returned and the contents are indeterminate. @see https:en.cppreference.com/w/c/chrono/strftime

See Also

  • https:en.cppreference.com/w/c/chrono/strftime
Publicfunction gmtime
func gmtime(timer : *time_t) : *tm
Converts given time since epoch (a time_t value pointed to by timer) into calendar time, expressed in Coordinated Universal Time (UTC) in the struct tm format. The result is stored in static storage and a pointer to that static storage is returned.

Parameters

  • timer - pointer to a time_t object to convert @return pointer to a static internal tm object on success, or null pointer otherwise. The structure may be shared between gmtime, localtime, and ctime and may be overwritten on each invocation. @see https:en.cppreference.com/w/c/chrono/gmtime

Returns

pointer to a static internal tm object on success, or null pointer otherwise. The structure may be shared between gmtime, localtime, and ctime and may be overwritten on each invocation. @see https:en.cppreference.com/w/c/chrono/gmtime

See Also

  • https:en.cppreference.com/w/c/chrono/gmtime
Publicfunction gmtime_r
func gmtime_r(timer : *time_t, buf : *tm) : *tm
Same as gmtime, except that the function uses user-provided storage buf for the result.

Parameters

  • timer - pointer to a time_t object to convert @param buf - pointer to a struct tm object to store the result @return copy of the buf pointer, or null pointer on error (which may be a runtime constraint violation or a failure to convert the specified time to UTC). @see https:en.cppreference.com/w/c/chrono/gmtime
  • buf - pointer to a struct tm object to store the result @return copy of the buf pointer, or null pointer on error (which may be a runtime constraint violation or a failure to convert the specified time to UTC). @see https:en.cppreference.com/w/c/chrono/gmtime

Returns

copy of the buf pointer, or null pointer on error (which may be a runtime constraint violation or a failure to convert the specified time to UTC). @see https:en.cppreference.com/w/c/chrono/gmtime

See Also

  • https:en.cppreference.com/w/c/chrono/gmtime
Publicfunction gmtime_s
func gmtime_s(timer : *time_t, buf : *tm) : *tm
Same as (1), except that the function uses user-provided storage buf for the result and that the following errors are detected at runtime and call the currently installed constraint handler function: timer or buf is a null pointer As with all bounds-checked functions, gmtime_s is only guaranteed to be available if __STDC_LIB_EXT1__ is defined by the implementation and if the user defines __STDC_WANT_LIB_EXT1__ to the integer constant 1 before including .

Parameters

  • timer - pointer to a time_t object to convert @param buf - pointer to a struct tm object to store the result @return copy of the buf pointer, or null pointer on error (which may be a runtime constraint violation or a failure to convert the specified time to UTC). @see https:en.cppreference.com/w/c/chrono/gmtime
  • buf - pointer to a struct tm object to store the result @return copy of the buf pointer, or null pointer on error (which may be a runtime constraint violation or a failure to convert the specified time to UTC). @see https:en.cppreference.com/w/c/chrono/gmtime

Returns

copy of the buf pointer, or null pointer on error (which may be a runtime constraint violation or a failure to convert the specified time to UTC). @see https:en.cppreference.com/w/c/chrono/gmtime

See Also

  • https:en.cppreference.com/w/c/chrono/gmtime
Publicfunction localtime
func localtime(timer : *time_t) : *tm
Converts given time since epoch (a time_t value pointed to by timer) into calendar time, expressed in local time, in the struct tm format. The result is stored in static storage and a pointer to that static storage is returned.

Parameters

  • timer - pointer to a time_t object to convert @param buf - pointer to a struct tm object to store the result @return pointer to a static internal tm object on success, or null pointer otherwise. The structure may be shared between gmtime, localtime, and ctime and may be overwritten on each invocation. @see https:en.cppreference.com/w/c/chrono/localtime
  • buf - pointer to a struct tm object to store the result @return pointer to a static internal tm object on success, or null pointer otherwise. The structure may be shared between gmtime, localtime, and ctime and may be overwritten on each invocation. @see https:en.cppreference.com/w/c/chrono/localtime

Returns

pointer to a static internal tm object on success, or null pointer otherwise. The structure may be shared between gmtime, localtime, and ctime and may be overwritten on each invocation. @see https:en.cppreference.com/w/c/chrono/localtime

See Also

  • https:en.cppreference.com/w/c/chrono/localtime
Publicfunction localtime_r
func localtime_r(timer : *time_t, buf : *tm) : *tm
Same as (1), except that the function uses user-provided storage buf for the result.

Parameters

  • timer - pointer to a time_t object to convert @param buf - pointer to a struct tm object to store the result @return copy of the buf pointer, or null pointer on error (which may be a runtime constraint violation or a failure to convert the specified time to local calendar time). @see https:en.cppreference.com/w/c/chrono/localtime
  • buf - pointer to a struct tm object to store the result @return copy of the buf pointer, or null pointer on error (which may be a runtime constraint violation or a failure to convert the specified time to local calendar time). @see https:en.cppreference.com/w/c/chrono/localtime

Returns

copy of the buf pointer, or null pointer on error (which may be a runtime constraint violation or a failure to convert the specified time to local calendar time). @see https:en.cppreference.com/w/c/chrono/localtime

See Also

  • https:en.cppreference.com/w/c/chrono/localtime
Publicfunction localtime_s
func localtime_s(timer : *time_t, buf : *tm) : *tm
Same as (1), except that the function uses user-provided storage buf for the result and that the following errors are detected at runtime and call the currently installed constraint handler function: timer or buf is a null pointer As with all bounds-checked functions, localtime_s is only guaranteed to be available if __STDC_LIB_EXT1__ is defined by the implementation and if the user defines __STDC_WANT_LIB_EXT1__ to the integer constant 1 before including .

Parameters

  • timer - pointer to a time_t object to convert @param buf - pointer to a struct tm object to store the result @return copy of the buf pointer, or null pointer on error (which may be a runtime constraint violation or a failure to convert the specified time to local calendar time). @see https:en.cppreference.com/w/c/chrono/localtime
  • buf - pointer to a struct tm object to store the result @return copy of the buf pointer, or null pointer on error (which may be a runtime constraint violation or a failure to convert the specified time to local calendar time). @see https:en.cppreference.com/w/c/chrono/localtime

Returns

copy of the buf pointer, or null pointer on error (which may be a runtime constraint violation or a failure to convert the specified time to local calendar time). @see https:en.cppreference.com/w/c/chrono/localtime

See Also

  • https:en.cppreference.com/w/c/chrono/localtime
Publicfunction mktime
func mktime(arg : *tm) : time_t
Renormalizes local calendar time expressed as a struct tm object and also converts it to time since epoch as a time_t object. arg->tm_wday and arg->tm_yday are ignored. The values in arg are not checked for being out of range. A negative value of arg->tm_isdst causes mktime to attempt to determine if Daylight Saving Time was in effect in the specified time. If the conversion to time_t is successful, the arg object is modified. All fields of arg are updated to fit their proper ranges. arg->tm_wday and arg->tm_yday are recalculated using information available in other fields.

Parameters

  • arg - pointer to a tm object specifying local calendar time to convert @return time since epoch as a time_t object on success, or -1 if arg cannot be represented as a time_t object (POSIX also requires EOVERFLOW to be stored in errno in this case). @see time since epoch as a time_t object on success, or -1 if arg cannot be represented as a time_t object (POSIX also requires EOVERFLOW to be stored in errno in this case).

Returns

time since epoch as a time_t object on success, or -1 if arg cannot be represented as a time_t object (POSIX also requires EOVERFLOW to be stored in errno in this case). @see time since epoch as a time_t object on success, or -1 if arg cannot be represented as a time_t object (POSIX also requires EOVERFLOW to be stored in errno in this case).

See Also

  • time since epoch as a time_t object on success, or -1 if arg cannot be represented as a time_t object (POSIX also requires EOVERFLOW to be stored in errno in this case).