How can I use the command line to boot to a specific OS when booting up

[fregoton]

I was wondering what commands to use to boot to a specific OS for example in case my OS gets corrupted and I am not able to use the graphical user interface but I have other OS installed on different partitions or maybe different hard drives how can I able to access these OSs from the command line

 

[iParanormalx]

You dont really need to use the command line for this..

With my experience if you have more than one OS installed on either different partitions or HDs and there is a boot record assigned to multiple partitions or drives in Windows Disk Management then when you boot you are prompted for which one you would like to start.

 

[carnageX]

Like iParanormal said, you don't use command line to boot to a specific OS. You select which OS you want from the bootloader. You can edit your bootloader from within Windows easily using EasyBCD: EasyBCD - NeoSmart Technologies

Or are you talking about the commands to recover / rebuild your bootloader if it gets corrupted? If so, then the command line commands for that are listed here:
How To Fix The Windows Bootloader » TweakHound