daylight, timezone, tzname, tzset - set timezone conversion information
[XSI] extern int daylight;
extern long timezone;
[CX] extern char *tzname;
The tzset() function shall use the value of the environment variable TZ to set time conversion information used by ctime , localtime , mktime , and strftime . If TZ is absent from the environment, implementation-defined default timezone information shall be used.
The tzset() function shall set the external variable tzname as follows:tzname = "std"; tzname = "dst";
where std and dst are as described in XBD Environment Variables .
[XSI] The tzset() function also shall set the external variable daylight to 0 if Daylight Savings Time conversions should never be applied for the timezone in use; otherwise, non-zero. The external variable timezone shall be set to the difference, in seconds, between Coordinated Universal Time (UTC) and local standard time.
The tzset() function shall not return a value.
No errors are defined.
Example TZ variables and their timezone differences are given in the table below:
ctime , localtime , mktime , strftime
XBD Environment Variables , <time.h>
First released in Issue 1. Derived from Issue 1 of the SVID.
The example is corrected.
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