_get_tzname
Retrieves the character string representation of the time zone name or the daylight standard time zone name (DST).
errno_t _get_tzname(
size_t* pReturnValue,
char* timeZoneName,
size_t sizeInBytes,
int index
);
Parameters
[out] pReturnValue
The string length of timeZoneName including a NULL terminator.[out] timeZoneName
The address of a character string for the representation of the time zone name or the daylight standard time zone name (DST), depending on index.[in] sizeInBytes
The size of the timeZoneName character string in bytes.[in] index
The index of one of the two time zone names to retrieve.
Return Value
Zero if successful, otherwise an errno type value.
If either timeZoneName is NULL, or sizeInBytes is zero or less than zero (but not both), an invalid parameter handler is invoked, as described in Parameter Validation. If execution is allowed to continue, this function sets errno to EINVAL and returns EINVAL.
Error Conditions
pReturnValue |
timeZoneName |
sizeInBytes |
index |
Return value |
Contents of timeZoneName |
---|---|---|---|---|---|
size of TZ name |
NULL |
0 |
0 or 1 |
0 |
not modified |
size of TZ name |
any |
> 0 |
0 or 1 |
0 |
TZ name |
not modified |
NULL |
> 0 |
any |
EINVAL |
not modified |
not modified |
any |
zero |
any |
EINVAL |
not modified |
not modified |
any |
> 0 |
> 1 |
EINVAL |
not modified |
Remarks
The _get_tzname function retrieves the character string representation of the time zone name or the daylight standard time zone name (DST) into the address of timeZoneName depending on the index value, along with the size of the string in pReturnValue. If timeZoneName is NULL and sizeInBytes is zero, just the size of the string of either time zone in bytes is returned in pReturnValue. The index values must be either 0 for standard time zone or 1 for daylight standard time zone; any other values of index have undetermined results.
Index values
index |
Contents of timeZoneName |
timeZoneName default value |
---|---|---|
0 |
Time zone name |
"PST" |
1 |
Daylight standard time zone name |
"PDT" |
> 1 or < 0 |
errno set to EINVAL |
not modified |
Unless the values are explicitly changed during run time, the default values are "PST" and "PDT" respectively. The sizes of these character arrays are governed by TZNAME_MAX value.
Requirements
Routine |
Required header |
---|---|
_get_tzname |
<time.h> |
For more information, see Compatibility.
.NET Framework Equivalent
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.