On 10/11/21 4:12 AM, Alejandro Colomar wrote:
time_t portable_timegm(struct tm *tm)
{
tm->tm_isdst = 0;
/*
* If another thread modifies the timezone during the
* execution of the line below, it will produce undefined
* behavior.
*/
return mktime(tm) - timezone;
}
This doesn't work for multiple reasons: it's not thread-safe, mktime might set timezone even in a single-threaded app, and the subtraction might overflow.
