tun: remove unused isUp method

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>

diff --git a/tun/tun_linux.go b/tun/tun_linux.go
index 7ab0623146623b148e89dcc8ad18ed82061ed78c..17b8822f92724639c2f7d97294319420fb647d4d 100644 (file)
--- a/tun/tun_linux.go
+++ b/tun/tun_linux.go
@@ -12,7 +12,6 @@ import (
        "bytes"
        "errors"
        "fmt"
-       "net"
        "os"
        "sync"
        "syscall"
@@ -164,11 +163,6 @@ func (tun *NativeTun) routineNetlinkListener() {
        }
 }
 
-func (tun *NativeTun) isUp() (bool, error) {
-       inter, err := net.InterfaceByName(tun.name)
-       return inter.Flags&net.FlagUp != 0, err
-}
-
 func getIFIndex(name string) (int32, error) {
        fd, err := unix.Socket(
                unix.AF_INET,