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Whenever I run fmt.Print("\033c") in Go on Windows cmd it does not clear screen but prints c whenever I do console.log("\033c") in javascript it works fine.

According to the following links this should have worked: https://en.wikipedia.org/wiki/ANSI_escape_code#Windows

https://learn.microsoft.com/en-us/windows/console/console-virtual-terminal-sequences#samples

I have tried logging it in javascript and it works fine I also tried adding a \n character to the end which printed c and changing it to \x1bc which also just printed: c

the following all prints: c on windows cmd


func main() {
  fmt.Print("\033c")
  fmt.Print("\033c\n")
  fmt.Print("\x1bc")
  fmt.Print("\x1bc\n")
  fmt.Println("\033c")
  fmt.Println("\x1bc")
}

I expected that it would just clear the screen as in javascript but for some reason it doesn't

To clarify I am talking about that the ANSI escape code is not working.

Jonathan Hall
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Ian.V
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  • fmt.Print("\033c") properly clears the screen on a "normal" terminal. Probably this is a Windows only problem. – Volker Jun 05 '19 at 12:49
  • There's a project on github, which seems to send `"\033[2J"` to the output to clear the screen. It's not explicitly mentioned, but might be worth a shot (see if it supports windows): [goterm](https://github.com/buger/goterm). There's a duplicate question about this, BTW: https://stackoverflow.com/questions/22891644/how-can-i-clear-the-terminal-screen-in-go – Elias Van Ootegem Jun 05 '19 at 15:55
  • Possible duplicate of [How can I clear the terminal screen in Go?](https://stackoverflow.com/questions/22891644/how-can-i-clear-the-terminal-screen-in-go) – Elias Van Ootegem Jun 05 '19 at 15:55
  • @EliasVanOotegem Thank you for your response, I have edited my question, I hope this clarifys that the ANSI escape code not working was the problem, I also answered my own question with the fix I found. – Ian.V Jun 06 '19 at 14:08

1 Answers1

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The problem was that windows needs the ENABLE_VIRTUAL_TERMINAL_PROCESSING(0x0004) console flag I fixed it by using the following code to add the flag to the console:

package main

// #include "Windows.h"
import "C"
import "fmt"

func main() {
    // Needed for getting handle and getting current console mode
    var mode C.DWORD
    handle := C.GetStdHandle(C.STD_OUTPUT_HANDLE)
    C.GetConsoleMode(handle, &mode)

    // Enable Virtual Terminal Processing by adding the flag to the current mode
    C.SetConsoleMode(handle, mode|0x0004)
    fmt.Print("\033c")
}

SetConsoleMode

===EDIT===

Like Matmarbon mentioned in the comments // #include "Windows.h" line is nessecary and you need to have an gcc installed

Ian.V
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    You have no idea how long it took me, to find this solution! Thank you! It is also worth mentioning for the beginners (like me) that the `// #include "Windows.h"` line is actually _necessary_ even though it looks like a comment. Also `gcc` should be installed - which I just did via MinGW and change of the `%PATH%` variable. – Matteo B. Aug 31 '19 at 22:19
  • @Matmarbon glad I could help and thank you for the tip I added it to the answer – Ian.V Sep 03 '19 at 11:53