Linux command
hwclock 命令
安全
权限或系统影响较大，执行前请核对目标。
常用示例
Example
sudo hwclock
Example
sudo hwclock -w
Example
sudo hwclock -s
Set hardware clock
sudo hwclock --set --date="2025-01-15 14:30:00"
Example
sudo hwclock --systohc --utc
Example
sudo hwclock --systohc --localtime
说明
hwclock reads and sets the hardware clock (Real-Time Clock/RTC), which is a battery-backed clock that maintains time when the system is powered off. The hardware clock can be set to either UTC or local time. Linux systems typically use UTC for the hardware clock and convert to local time for display. Dual-boot systems with Windows may need the hardware clock in local time since Windows expects this. During boot, the system typically runs hwclock --hctosys to initialize system time from the hardware clock. NTP then corrects for any drift.
参数
- -r, --show
- Read and display hardware clock time
- -w, --systohc
- Set hardware clock from system time
- -s, --hctosys
- Set system time from hardware clock
- --set --date=_TIME_
- Set hardware clock to specified time
- --localtime
- Hardware clock is in local time
- --utc
- Hardware clock is in UTC
- --adjust
- Adjust for systematic drift
- --verbose
- Show detailed information about what hwclock is doing
- --test
- Dry run; show what would be done without modifying anything
- -f, --rtc _FILE_
- Use specified RTC device (default: /dev/rtc0)
FAQ
What is the hwclock command used for?
hwclock reads and sets the hardware clock (Real-Time Clock/RTC), which is a battery-backed clock that maintains time when the system is powered off. The hardware clock can be set to either UTC or local time. Linux systems typically use UTC for the hardware clock and convert to local time for display. Dual-boot systems with Windows may need the hardware clock in local time since Windows expects this. During boot, the system typically runs hwclock --hctosys to initialize system time from the hardware clock. NTP then corrects for any drift.
How do I run a basic hwclock example?
Run `sudo hwclock` in a terminal, then adjust file names, paths, flags, or remote targets for your system.
What does -r, --show do in hwclock?
Read and display hardware clock time