term: remove duplicate flag and add comment on windows

Both windows.ENABLE_PROCESSED_INPUT and windows.ENABLE_PROCESSED_OUTPUT have
the same value of 0x1. Using makeRaw on a console output screen buffer handle
wouldn't make sense since on Windows the input handle and the output screen
buffer handle are two separate things.

See https://learn.microsoft.com/en-us/windows/console/setconsolemode

Change-Id: I19feadf8da303a1ada8e517399416a4730845900
GitHub-Last-Rev: 832fc7e
GitHub-Pull-Request: #14
Reviewed-on: https://go-review.googlesource.com/c/term/+/562779
Reviewed-by: Michael Pratt <[email protected]>
Reviewed-by: Laurent Demailly <[email protected]>
Reviewed-by: Jorropo <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Cherry Mui <[email protected]>

Author: aymanbagabas

term_windows.go

@@ -20,12 +20,14 @@ func isTerminal(fd int) bool {
 	return err == nil
 }
 
+// This is intended to be used on a console input handle.
+// See https://learn.microsoft.com/en-us/windows/console/setconsolemode
 func makeRaw(fd int) (*State, error) {
 	var st uint32
 	if err := windows.GetConsoleMode(windows.Handle(fd), &st); err != nil {
 		return nil, err
 	}
-	raw := st &^ (windows.ENABLE_ECHO_INPUT | windows.ENABLE_PROCESSED_INPUT | windows.ENABLE_LINE_INPUT | windows.ENABLE_PROCESSED_OUTPUT)
+	raw := st &^ (windows.ENABLE_ECHO_INPUT | windows.ENABLE_PROCESSED_INPUT | windows.ENABLE_LINE_INPUT)
 	raw |= windows.ENABLE_VIRTUAL_TERMINAL_INPUT
 	if err := windows.SetConsoleMode(windows.Handle(fd), raw); err != nil {
 		return nil, err