Overwrite file extension

[abolinhas]

Hi
I want to write an INI file type with .conf extension.
https://web.mit.edu/kerberos/krb5-1.11/doc/admin/conf_files/krb5_conf.html

I'm trying this but returns a error

main.go
package main
import(
"github.com/spf13/viper"
"fmt"
)

func main(){
vp := viper.New()
        vp.SetConfigName("smb")
        vp.SetConfigType("ini")
        vp.Set("global.netbios name", "1")
        vp.Set("global.log level", "2")
        vp.Set("global.workgroup", "3")
err := vp.WriteConfigAs("/root/viper/smb.conf")
fmt.Println(err)
}

root@proxy02:~# go run main.go
Unsupported Config Type "conf"

I also tried to add conf extension to allowed extention, this not return any error but creates a empty conf file.

package main
import(
"github.com/spf13/viper"
"fmt"
)

func main(){
vp := viper.New()
viper.SupportedExts=append(viper.SupportedExts,"conf")
        vp.SetConfigName("smb")
        vp.SetConfigType("ini")
        vp.Set("global.netbios name", "1")
        vp.Set("global.log level", "2")
        vp.Set("global.workgroup", "3")
err := vp.WriteConfigAs("/root/viper/smb.conf")
fmt.Println(err)
}

If I use vp.WriteConfigAs("/root/viper/smb.ini") everything work as expected.

So my question is, it's possible overwrite file extension for a specific file type? In this case my config type is INI and I want the file name to be smb.conf.

Best regards