How to identify /3GB switch?

NTDEV
1

Hi All,

How can I identify programatically that the operating system is booted with /3GB switch?

Thanks & Regards,
Amit.

2

There may be a better way - in particular one that does not involve parsing in the kernel - but one way is to look at the REG_SZ value:

\Registry\Machine\System\CurrentControlSet\Control:SystemStartOptions

It contains the switches/bcd settings in a space separated list. Based on looking at only one XP and one Server 2008 system, it appears that the later include the slash (/) in front of each option, the irony being that they aren’t used on Vista. In any case, if you go this route, you’ll have to take a better look at this.

Good luck,

mm

3

HKLM\SYSTEM\CurrentControlSet\Control\SystemStartOptions

Will have a /3GB there. Just read the registry.

Regards
anand

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Subject: [ntdev] How to identify /3GB switch?

Hi All,

How can I identify programatically that the operating system is booted
with /3GB switch?

Thanks & Regards,
Amit.

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4

Check out the bottom of http://msdn2.microsoft.com/en-us/library/bb613473.aspx for some ideas.

  • Danilo