localtime_r(3)                                           localtime_r(3)

  localtime()

  NAME

    localtime(), localtime_r() - transform timer data into timer structure in
    local time

  SYNOPSIS

    #include 

    struct tm * localtime (const time_t *clock)

    struct tm *localtime_r (const time_t *clock,
           struct tm *result)

  DESCRIPTION

    The localtime(3) function takes as an argument a time value representing
    the time in seconds since the Epoch (00:00:00 UTC, January 1, 1970; see
    time(2)). It converts the time value pointed at by clock, and returns a
    pointer to a struct tm (described below) which contains the broken-out
    time information for the value after adjusting for the current time zone
    (and any other factors such as Daylight Saving Time). Time zone
    adjustments are performed as specified by the TZ environment variable (see
    tzset(3)). The function localtime(3) uses tzset(3) to initialize time
    conversion information if tzset(3) has not already been called by the
    process.

    After filling in the tm structure, localtime(3) sets the tm_isdst element
    of tzname to a pointer to an ASCII string that's the time zone
    abbreviation to be used with localtime(3)'s return value.

    External declarations as well as the tm structure definition are in the
     include file. The tm structure includes at least the following
    fields:
    int     tm_sec;       seconds (0 - 60)

    int     tm_min;       minutes (0 - 59)

    int     tm_hour;      hours (0 - 23)

    int     tm_mday;      day of month (1 - 31)

    int     tm_mon;       month of year (0 - 11)

    int     tm_year;      year - 1900

    int     tm_wday;      day of week (Sunday = 0)

    int     tm_yday;      day of year (0 - 365)

    int     tm_isdst;     is summer time in effect?

    The field tm_isdst is non-zero if summer time is in effect.

    The reentrant localtime_r(3) function converts the time in seconds since
    the Epoch pointed to by clock into a broken-down time and stores the
    broken-down time in the structure identified by result. On success, the
    localtime_r(3) function also returns the address of the same structure;
    otherwise, it returns a null pointer.

  SEE ALSO

    date(1)

    asctime(3)

    ctime(3)

    gmtime(3)

    mktime(3)

    difftime(3)

    getenv(3)

    time(2)

    tzset(3)

  USAGE NOTES

    The localtime_r function is thread safe. The localtime function is not
    thread safe.

    None of these functions are async-signal safe.