timeval에 관해 질문 드립니다.

[bushi@rose ~]$ /sbin/hwclock --help
hwclock - query and set the hardware clock (RTC)
 
Usage: hwclock [function] [options...]
 
Functions:
  --help        show this help
  --show        read hardware clock and print result
  --set         set the rtc to the time given with --date
  --hctosys     set the system time from the hardware clock
  --systohc     set the hardware clock to the current system time
  --adjust      adjust the rtc to account for systematic drift since 
                the clock was last set or adjusted
  --getepoch    print out the kernel's hardware clock epoch value
  --setepoch    set the kernel's hardware clock epoch value to the 
                value given with --epoch
  --version     print out the version of hwclock to stdout
 
Options: 
  --utc         the hardware clock is kept in coordinated universal time
  --localtime   the hardware clock is kept in local time
  --rtc=path    special /dev/... file to use instead of default
  --directisa   access the ISA bus directly instead of /dev/rtc
  --badyear     ignore rtc's year because the bios is broken
  --date        specifies the time to which to set the hardware clock
  --epoch=year  specifies the year which is the beginning of the 
                hardware clock's epoch value
  --noadjfile   do not access /etc/adjtime. Requires the use of
                either --utc or --localtime
[bushi@rose ~]$