How to Convert a Hex DWord Registry Value into Four Octets

Keywords:    octet RegQueryDWord Hex

Question:

I'm trying to pull DHCP scope information from the registry and put it into a file so that it's easier to read. We have 200+ scopes on this server and using the GUI is impossible.
Briefly: the script uses RegQueryKeys to get the values of all the keys under @RegMachine of the DHCP server. It then formats that as a crlf-delimited file, which I open as if its an array, walk down the array and use the data to open each scope. I then pull out from each scope the data. An example follows:
handle=RegConnect("172.16.5.242", @REGMACHINE) startaddress=RegQueryDword(handle,"SYSTEM\CurrentControlSet\Services\DHCPServer\Configuration\Subnets\172.16.0.0\IPRanges\172.16.50.1[StartAddress]")
The actual value sitting at that registry key is a hex value of ac103201, but when I run the script with debug on, the query returns the value of -1408224767. I tried converting ac103201 to decimal with xbaseconvert and I get the same result. Converting -1408227467 to hex does not get the original hex number. The actual decimal number found on the registry radix is 2886742529, and the binary of that is 10101100000100000011001000000001.
If I convert the -140xxx number to binary, I get of course completely different results. What's happening, it looks like, is sort of like when you use the wrong integer type in C or C++ and it wraps around to a negative number -- like xbaseconvert takes as its input a short int instead of a long int.

Is there a way around this? I'd like to be able to pull the original hex number out as a string, not a number, and break it into the four octets before using xbaseconvert to process it.

Answer:

Try:

;Rvalue is value from RegQueryDword

rvalue=-1408224767
octet1= (rvalue >> 24) & 255
octet2= (rvalue >> 16) & 255
octet3= (rvalue >> 8) & 255
octet4= (rvalue) & 255

dottedquad=strcat(octet1,".",octet2,".",octet3,".",octet4)
Message(rvalue,dottedquad)

That should return something like 172.16.50.1, which is in real fact the starting address for that scope.

Article ID:   W13715

Filename:   Converting a Hex DWord Value into Four Octets.txt

File Created: 1999:04:15:16:55:54

Last Updated: 1999:04:15:16:55:54

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How to Convert a Hex DWord Registry Value into Four Octets

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