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i just not know how to use mem command in BSD to access physical memory or virtual memory to get the ACPI tables and their Address .......

$mem Enter mem command not found ....

so what can i do ?

is any body can give me clarification on this command how to use and what result it wil give and all....

please help me in this i am struggling from past three day on this ?

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There's no mem command, not sure why you would think there is... You're probably looking for kdbg and it's dump memory command. In kdbg enter help $cmd (where $cmd is a command) for more help.

There is a /dev/mem special device that represents physical memory. You can read and write to this device, specifically you might be interested in using dd to copy chunks out.

Both of these require root access and both are easily capable of crashing or corrupting memory.
Be careful using them.

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thank you ! boss i think i have to be clear on this topic ?? – gkreddy Aug 8 '13 at 5:27

you can use:

sysctl hw.physmem

Then there is also:

su-3.2# grep memory /var/run/dmesg.boot

usable memory = 8571846656 (8174 MB)

avail memory = 8270299136 (7887 MB)


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I'm pretty sure that's completely not what he's asking for. – Chris S Aug 7 '13 at 15:58
yes! answer is Completely not What i wanted !!! – gkreddy Aug 8 '13 at 10:15

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