OpenProcess: The parameter is incorrect.

[danawoodman]

I am getting the error OpenProcess: The parameter is incorrect. when trying to run overseer.Stop(id) on a process running on a Windows VM.

Any ideas why this might be the case? I'm unable to stop processes running on Windows machines including using the example program.

Here is the full reproducible test code:

package main

import (
	"fmt"
	"os"
	"time"

	cmd "github.com/ShinyTrinkets/overseer"
)

func main() {
	ovr := cmd.NewOverseer()

	// Disable output buffering, enable streaming
	cmdOptions := cmd.Options{
		Buffered:   false,
		Streaming:  true,
		DelayStart: 1,
		RetryTimes: 9999999,
	}

	// Add Cmd with options
	id1 := "ping1"
	pingCmd := ovr.Add(id1, "ping", []string{"-t", "localhost"}, cmdOptions)
	pingCmd.Start()

	statusFeed := make(chan *cmd.ProcessJSON)
	ovr.Watch(statusFeed)

	// Capture status updates from the command
	go func() {
		for state := range statusFeed {
			fmt.Printf("STATE: %v\n", state)
		}
	}()

	// Capture STDOUT and STDERR lines streaming from Cmd
	// If you don't capture them, they will be written into
	// the overseer log to Info or Error.
	go func() {
		ticker := time.NewTicker(100 * time.Millisecond)
		for {
			select {
			case line := <-pingCmd.Stdout:
				fmt.Println(line)
			case line := <-pingCmd.Stderr:
				fmt.Fprintln(os.Stderr, line)
			case <-ticker.C:
				if !ovr.IsRunning() {
					fmt.Println("Closing Stdout and Stderr loop")
				}
			}
		}
	}()

	go func() {
		time.Sleep(5 * time.Second)
		fmt.Println("stopping!")
		err := ovr.Stop(id1)
		if err != nil {
			panic(err)
		}
	}()

	// Run and wait for all commands to finish
	ovr.SuperviseAll()

	// Even after the command is finished, you can still access detailed info
	time.Sleep(100 * time.Millisecond)
	fmt.Println(ovr.Status(id1))
}

Should just be able to run the built program on a Windows machine and after 5 seconds the panic will trigger.

Here are some links with info:

• Failer on windows when pid is from dead process nightlyone/lockfile#10
• https://docs.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-openprocess?redirectedfrom=MSDN
• 'The parameter is incorrect' when try to raw_exec any exe hashicorp/nomad#1112
  • Points to this change, not sure if relevant: https://github.com/hashicorp/nomad/pull/1115/files

[croqaz]

Hi !
Thanks for rasining this issue. I can't reproduce it because I have no Windows computer anywhere near. And I don't plan on supporting Windows for Overseer.
You're probably right that some functions behave differently on Windows vs Other.
If you find a portable way to fix this, I'll gladly review your PR. Let me know.

[navono]

The whole Cmd implemented in overseer is based on Linux, doesn't match Windows. So, even correction the pid that pass to os.FindProcess, the proc.Signal also cause another error. Simply put, overseer not all features support Windows. Perhaps having this documented in the README might dispel some doubts.

[croqaz]

Thank you for the PR @navono !
Also you're right I should have mentioned about the Windows support, I'll mention in the README.
I'll check your code later this weekend, I hope :) But the tests are passing, so that's a good sign!

[croqaz]

Hi @danawoodman .
I hope you don't mind if I close this issue, because it doesn't seem to be relevant anymore.
Feel free to create another issue if you still use Overseer.
Thank you!