.TZDOFF - offset between standard and daylight time.

Alternate Entry Name: _TZDOFF

Usage:

B:
   %b/manif/t_ctrl
   offset = .tzdoff( tloc, timenum );

C:
   #include <t_ctrl.h>
   long _tzdoff(_T_locale tloc, time_t timenum);

Examples:

ouroffset = .tzdoff(tloc, .ctime());

Where:

tloc

is a time zone locale reference value.

timenum

is a time expressed as a number of seconds from 0:00 a.m. on January 1, 1970 (returned by the C "time" function or by B functions like .CTIME, .MKTIME, or .TOSEC).

offset

is an offset in minutes.

Description:

If the locale given by "tloc" is using standard time on the date and time given by "timenum", .TZDOFF returns zero. If the locale is using daylight time on that date and time, .TZDOFF returns the difference between the daylight time and standard time (usually 60, indicating that daylight time is one hour ahead of the locale's standard time).

See Also:

expl b tz

for background on time zones.

expl b lib .tosec

to convert an arbitrary time to a number of seconds from January 1, 1970.

expl c lib time

to obtain the current time as a number of seconds.

Copyright © 1996, Thinkage Ltd.