Hi All, I'm strugling with the C-function mktime. According to the man-pages it returns "seconds since the Epoch". I tried to use this functions to get differnces from two date-times , but was could not interpret the result. When trying to get the diffrence between 30 Nov 2019 23:59:59 and 1 Dec 2019 00:00:00 (see code below) I expected to find 1 second difference but I find: 1577746799 1577833200 -86401 As output of the sample program. (and not 1577833199 1577833200 -1) How should I read "seconds since the Epoch"???? Is the output of mktime correct? (I also tried 31 Nov and got the expected 1 second) (should mktime not give an error for 31 Nov??) Regards Jouk Code : #include <stdio.h> #include <time.h> main() { struct tm time_str , time_str2; time_str.tm_sec = 59; //30 Nov 2019 23:59:59 time_str.tm_min = 59; time_str.tm_hour = 23; time_str.tm_mday = 30; time_str.tm_mon = 11; time_str.tm_year = 119; time_str.tm_isdst = 0; time_str2.tm_sec = 0; // 1 Dec 2019 00:00:00 time_str2.tm_min = 0; time_str2.tm_hour = 0; time_str2.tm_mday = 1; time_str2.tm_mon = 12; time_str2.tm_year = 119; time_str2.tm_isdst = 0; printf( "%d %d %d\n" , mktime( &time_str ) , mktime( &time_str2 ) , mktime( &time_str ) - mktime( &time_str2 ) ); } Pax, vel iniusta, utilior est quam iustissimum bellum. (free after Marcus Tullius Cicero (106 b.Chr.-46 b.Chr.) Epistularum ad Atticum 7.1.4.3) Touch not the cat bot a glove >------------------------------------------------------------------------------< Jouk Jansen joukj@xxxxxxxxxxxxxxxxxxxx Technische Universiteit Delft tttttttttt uu uu ddddddd Kavli Institute of Nanoscience tttttttttt uu uu dd dd Nationaal centrum voor HREM tt uu uu dd dd Lorentzweg 1 tt uu uu dd dd 2628 CJ Delft tt uu uu dd dd Nederland tt uu uu dd dd tel. 31-15-2782272 tt uuuuuuu ddddddd >------------------------------------------------------------------------------< _______________________________________________ users mailing list -- users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to users-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@xxxxxxxxxxxxxxxxxxxxxxx