How to use syscall to query and manipulate system time and date settings in Golang?

In Go, the syscall package provides access to low-level system calls. To query and manipulate system time and date settings, you can use the Syscall() function from the syscall package along with specific system calls defined for your operating system.

Here's an example of how you can use syscall to query and manipulate system time and date settings in Go:

package main

import (
	"fmt"
	"syscall"
	"time"
)

func main() {
	// Get the current system time
	var tv syscall.Timeval
	if err := syscall.Gettimeofday(&tv); err != nil {
		fmt.Println("Error getting system time:", err)
		return
	}
	seconds := tv.Sec
	nanoseconds := tv.Usec * 1000
	sysTime := time.Unix(seconds, nanoseconds)
	fmt.Println("System time:", sysTime)

	// Set the system time
	newTime := time.Date(2022, time.January, 1, 0, 0, 0, 0, time.UTC)
	tv = syscall.NsecToTimeval(newTime.UnixNano())
	if err := syscall.Settimeofday(&tv); err != nil {
		fmt.Println("Error setting system time:", err)
		return
	}
	fmt.Println("System time set to:", newTime)
}

In this example, we first use Gettimeofday() to get the current system time. The Gettimeofday() system call fills the tv variable with the seconds and microseconds since the epoch. We convert the values into a Go time.Time struct.

Then, we set a new time using time.Date() to represent January 1, 2022, at midnight (UTC). We convert this new time into a syscall.Timeval struct using NsecToTimeval() to set the system time using the Settimeofday() system call.

Note that this example assumes you are running on a Unix-like operating system that supports the gettimeofday and settimeofday system calls. If you are on a different operating system, you'll need to find the appropriate system calls for your platform and adjust the code accordingly.