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I'm running Centos 6.3 on a Dell laptop, I'm not running a graphical desktop - just text mode. When I shut the laptop lid the display remains active with the backlight on, whereas I'm expecting it should switch off and back on when I open the lid.

ACPI events are being received and acpid is running.

What command can switch the display & backlight off and on? Is there an acpi action script that can do the job for me?

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This worked for my CentOS on a Dell laptop:

vbetool dpms off

See specifically, see the daemon script referenced under the "Display Backlight Control" section. That is where I found the above command. To be honest I do not just how "vbetool" does its magic with the BIOS and all, although I encourage you to check the man page for it. It can be installed through yum, btw, and runs regardless of whether X windows is installed. Obviously use the 'on' parameter to turn the monitor back on.

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Hello, welcome to Superuser. Your answer is a little sparse on details. It relies too much on a linked page, which covers a lot of stuff besides the topic at hand. Also, we try to be an information repository, so a good answer needs more than a bare link. Please try to improve your answer, or it's likely to be deleted. – Isaac Rabinovitch May 22 '13 at 2:43

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