Ask Your Question

'outb' Command Unknown in Grub

asked 2013-06-02 04:02:49 -0500

Keith Ó Dúlaigh gravatar image

updated 2014-04-11 15:48:50 -0500

remjg gravatar image


When using EFI booting with GRUB on Ubuntu and Linux Mint I am able to include "outb" commands in my grub config file to write values to particular memory addresses. But on Fedora 18 this gives a command not known warning.

Can anyone suggest how to get outb working?

Thanks, Keith

edit retag flag offensive close merge delete


Keith, comment about what you're trying to accomplish by calling outb in grub? We might be able to better help with more information about your goals.

randomuser gravatar imagerandomuser ( 2013-06-03 00:49:48 -0500 )edit

1 Answer

Sort by » oldest newest most voted

answered 2013-06-02 20:29:53 -0500

$ yum provides \*bin/outb
Loaded plugins: langpacks, presto, refresh-packagekit
ioport-1.2-6.fc18.x86_64 : Access I/O ports
Repo        : fedora
Matched from:
Filename    : /usr/bin/outb

Is this what you're looking for?

edit flag offensive delete link more


Hi randomuser, not quite. I want to send commands to the multiplexer in my laptop to switch off the Radeon graphics card. I have vgaswitcheroo working but it's a bit flaky and I think using outb commands from grub will help.

Keith Ó Dúlaigh gravatar imageKeith Ó Dúlaigh ( 2013-06-07 04:54:01 -0500 )edit

Question Tools



Asked: 2013-06-02 04:02:49 -0500

Seen: 680 times

Last updated: Jun 02 '13