TIMEGM(3) Linux Programmer's Manual TIMEGM(3)

NAME
       timegm, timelocal - inverses for gmtime and localtime

SYNOPSIS
       ##iinncclluuddee <>

       ttiimmeett ttiimmeellooccaall ((ssttrruucctt ttmm **tm));;

       ttiimmeett ttiimmeeggmm ((ssttrruucctt ttmm **tm));;

DESCRIPTION
       The functions ttiimmeellooccaall(()) and ttiimmeeggmm(()) are the inverses to llooccaallttiimmee(3)
       and ggmmttiimmee(3).

NNOOTTEESS
       These functions are GNU extensions.  The ttiimmeellooccaall(()) function is equiv-
       alent  to the POSIX standard function mmkkttiimmee(3).  There is no reason to
       ever use it.

       For a portable version of ttiimmeeggmm(()), set the TTZZ environment variable  to
       UTC, call mmkkttiimmee(()) and restore the value of TTZZ.  Something like

              #include 
              #include 

              timet mytimegm (struct tm *tm) {
                  timet ret;
                  char *tz;

                  tz = getenv("TZ");
                  setenv("TZ", "", 1);
                  tzset();
                  ret = mktime(tm);
                  if (tz)
                      setenv("TZ", tz, 1);
                  else
                      unsetenv("TZ");
                  tzset();
                  return ret;
              }

SEE ALSO
       ggmmttiimmee(3), llooccaallttiimmee(3), mmkkttiimmee(3), ttzzsseett(3)



GNU                               2001-12-26                         TIMEGM(3)