(0003611)
geoffclare (manager)
2017-03-07 15:52
|
The intention is that strftime() must update tzname[].
This was stated explicitly in POSIX.1-1990 and POSIX.1-1996 in section 8.1.1 after the description of the TZ rules:Whenever ctime(), strftime(), mktime(), or localtime() is called, the time zone names contained in the external variable tzname shall be set as if the tzset() function had been called.
However, the merge with SUS in 2001 did not retain this statement with the TZ description in XBD, instead relying on the "as though" statements in the individual function descriptions.
There is also this statement in the tzset() APPLICATION USAGE section:Since the ctime(), localtime(), mktime(), strftime(), and strftime_l() functions are required to set timezone information as if by calling tzset(), there is no need for an explicit tzset() call before using these functions. However, portable applications should call tzset() explicitly before using ctime_r() or localtime_r() because setting timezone information is optional for those functions.
Note that the "as though" wording on the strftime() page is exactly the same as on the localtime() page, and I assume nobody would question the requirement for localtime() to set tzname[]. Interestingly, the mktime() page has slightly different wording:Local timezone information shall be set as though mktime() called tzset().
I suggest that we should change the localtime() and strftime() pages to use this wording. |
(0004084)
Don Cragun (manager)
2018-08-16 16:17
|
In localtime() DESCRIPTION section on P1265, L42209-42210, change:
Local timezone information is used as though localtime() calls tzset().
to:
Local timezone information shall be set as though localtime() called tzset().
In strftime() DESCRIPTION section on P2045, L65543, change:
Local timezone information is used as though strftime() calls tzset().
to:
Local timezone information shall be set as though strftime() called tzset(). |