16 replies to this topic

[Zinthose]

I needed a way to HexEdit / Patch a file to repair a common file corruption problem in a software package my company uses. I first used the AutoIt core FileOpen / FileWrite functions but this method required me to open the whole file into memory. The files I work with can be several hundred megabytes in size and easily cause out of memory errors. So, After searching / hacking I came up with this solution.

I hope someone finds it useful

AutoIt        expandcollapse  popup

#include <WinAPI.au3>

_Demo()

Func _Demo()
    Local Const $TestFile_Path = @ScriptDir & "\Test.Bin"
    Local $TestFile_ID, $bData, $Offset
   
    ;## Hex offsets / lengths of the data stored in the file.
        Local Const $Offset_Phone[2]    = [0x012,  4]
        Local Const $Offset_NewToy[2]   = [0x1b6, 18]
        Local Const $Offset_Recycle[2]  = [0x594, 24]

    ;## Binary string of the test file.
        Local Const $TestFile_Data = "0x" & _
            "42494E000000000000000000000000000000867530900000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000446F6E27742054617A65206D" & _
            "652042726F21000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000536F796C656E742067726565" & _
            "6E2069732070656F706C6521000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000"

    ;## Create Test File
        $TestFile_ID = FileOpen($TestFile_Path, 14)
        FileWrite($TestFile_ID, Binary($TestFile_Data))
        FileClose($TestFile_ID)
       
    ;## Read the Recycle Value
        $bData = _HexRead($TestFile_Path, $Offset_Recycle[0], $Offset_Recycle[1])
   
    ;## Convert data to a string and display.
        MsgBox(4096, Default, "Recycle:" & @CRLF & BinaryToString($bData))
   
    ;## Change the recycle value
        $bData = StringToBinary("It Tastes like chicken!!")
        _HexWrite($TestFile_Path, $Offset_Recycle[0], $bData)
   
    ;## Read the Recycle Value
        $bData = _HexRead($TestFile_Path, $Offset_Recycle[0], $Offset_Recycle[1])
   
    ;## Convert data to a string and display.
        MsgBox(4096, Default, "Recycle:" & @CRLF & BinaryToString($bData))
        
    ;## Search for a specific value and display
        $Offset = _HexSearch($TestFile_Path, $bData)
        MsgBox(4096, "HexSearch Function", "Search performed to locate data stream: " & @CRLF & @TAB & $bData & @CRLF & "Result = 0x" & Hex($Offset, 3))        
   
EndFunc

#Region ;**** HexEdit Functions
    
    Func _HexWrite($FilePath, $Offset, $BinaryValue)
        Local $Buffer, $ptr, $bLen, $fLen, $hFile, $Result, $Written
        
        ;## Parameter Checks
            If Not FileExists($FilePath)    Then    Return SetError(1, @error, 0)
            $fLen = FileGetSize($FilePath)
            If $Offset > $fLen              Then    Return SetError(2, @error, 0)
            If Not IsBinary($BinaryValue)   Then    Return SetError(3, @error, 0)
            $bLen = BinaryLen($BinaryValue)
            If $bLen > $Offset + $fLen      Then    Return SetError(4, @error, 0)
        
        ;## Place the supplied binary value into a dll structure.
            $Buffer = DllStructCreate("byte[" & $bLen & "]")
        
            DllStructSetData($Buffer, 1, $BinaryValue)
            If @error Then Return SetError(5, @error, 0)
        
            $ptr = DllStructGetPtr($Buffer)
        
        ;## Open File
            $hFile = _WinAPI_CreateFile($FilePath, 2, 4, 0)
            If $hFile = 0 Then Return SetError(6, @error, 0)
        
        ;## Move file pointer to offset location
            $Result = _WinAPI_SetFilePointer($hFile, $Offset)
            $err = @error
            If $Result = 0xFFFFFFFF Then
                _WinAPI_CloseHandle($hFile)
                Return SetError(7, $err, 0)
            EndIf
            
        ;## Write new Value
            $Result = _WinAPI_WriteFile($hFile, $ptr, $bLen, $Written)
            $err = @error
            If Not $Result Then
                _WinAPI_CloseHandle($hFile)
                Return SetError(8, $err, 0)
            EndIf
        
        ;## Close File
            _WinAPI_CloseHandle($hFile)
            If Not $Result Then Return SetError(9, @error, 0)
    EndFunc

    Func _HexRead($FilePath, $Offset, $Length)
        Local $Buffer, $ptr, $fLen, $hFile, $Result, $Read, $err, $Pos
        
        ;## Parameter Checks
            If Not FileExists($FilePath)    Then    Return SetError(1, @error, 0)
            $fLen = FileGetSize($FilePath)
            If $Offset > $fLen              Then    Return SetError(2, @error, 0)
            If $fLen < $Offset + $Length    Then    Return SetError(3, @error, 0)

        ;## Define the dll structure to store the data.
            $Buffer = DllStructCreate("byte[" & $Length & "]")
            $ptr = DllStructGetPtr($Buffer)
        
        ;## Open File
            $hFile = _WinAPI_CreateFile($FilePath, 2, 2, 0)
            If $hFile = 0 Then Return SetError(5, @error, 0)
        
        ;## Move file pointer to offset location
            $Pos = $Offset
            $Result = _WinAPI_SetFilePointer($hFile, $Pos)
            $err = @error
            If $Result = 0xFFFFFFFF Then
                _WinAPI_CloseHandle($hFile)
                Return SetError(6, $err, 0)
            EndIf
            
        ;## Read from file
            $Read = 0
            $Result = _WinAPI_ReadFile($hFile, $ptr, $Length, $Read)
            $err = @error
            If Not $Result Then
                _WinAPI_CloseHandle($hFile)
                Return SetError(7, $err, 0)
            EndIf
        
        ;## Close File
            _WinAPI_CloseHandle($hFile)
            If Not $Result Then Return SetError(8, @error, 0)
            
        ;## Return Data
            $Result = DllStructGetData($Buffer, 1)
            
            Return $Result
    EndFunc

    Func _HexSearch($FilePath, $BinaryValue, $StartOffset = Default)    
        Local $Buffer, $ptr, $hFile, $Result, $Read, $SearchValue, $Pos, $BufferSize = 2048
        
        ;## Parameter Defaults
            If $StartOffset = Default       Then    $StartOffset = 0
        
        ;## Parameter Checks
            If Not FileExists($FilePath)    Then    Return SetError(1, @error, 0)
            $fLen = FileGetSize($FilePath)
            If $StartOffset > $fLen         Then    Return SetError(2, @error, 0)
            If Not IsBinary($BinaryValue)   Then    Return SetError(3, @error, 0)
            If Not IsNumber($StartOffset)   Then    Return SetError(4, @error, 0)
        
        ;## Prep the supplied binary value for search
            $SearchValue = BinaryToString($BinaryValue)
        
        ;## Define the dll structure to store the data.
            $Buffer = DllStructCreate("byte[" & $BufferSize & "]")
            $ptr = DllStructGetPtr($Buffer)

        ;## Open File
                $hFile = _WinAPI_CreateFile($FilePath, 2, 2, 1)
                If $hFile = 0 Then Return SetError(5, @error, 0)
            
        ;## Move file pointer to offset location
            $Result = _WinAPI_SetFilePointer($hFile, $StartOffset)
            $err = @error
            If $Result = 0xFFFFFFFF Then
                _WinAPI_CloseHandle($hFile)
                Return SetError(5, $err, 0)
            EndIf
            
        ;## Track the file pointer's position
            $Pos = $StartOffset
            
        ;## Start Search Loop
            While True
                
                ;## Read from file
                    $Read = 0
                    $Result = _WinAPI_ReadFile($hFile, $ptr, $BufferSize, $Read)
                    $err = @error
                    If Not $Result Then
                        _WinAPI_CloseHandle($hFile)
                        Return SetError(6, $err, 0)
                    EndIf
                
                ;## Prep read data for search
                    $Result = DllStructGetData($Buffer, 1)
                    $Result = BinaryToString($Result)
                
                ;## Search the read data for first match
                    $Result = StringInStr($Result, $SearchValue)
                    If $Result > 0 Then ExitLoop
                
                ;## Test for EOF and return -1 to signify value was not found
                    If $Read < $BufferSize Then
                        _WinAPI_CloseHandle($hFile)
                        Return -1
                    EndIf
                
                ;## Value not found, Continue Tracking file pointer's position
                    $Pos += $Read
                    
            WEnd

        ;## Close File
            _WinAPI_CloseHandle($hFile)
            If Not $Result Then Return SetError(7, @error, 0)
            
        ;## Calculate the offset and return
            $Result = $Pos + $Result - 1
            Return $Result
    EndFunc

    Func _WinAPI_SetFilePointer($hFile, $nDistance, $nMethod = 0)
        Local $nRet
        $nRet = DllCall("kernel32.dll", "dword", "SetFilePointer", "ptr", $hFile, "long", $nDistance, "ptr", 0, "dword", $nMethod)
        
        Return $nRet[0]
    EndFunc

#EndRegion

** UPDATES **

• Added new function: _HexSearch()

Edited by Zinthose, 21 November 2008 - 09:47 PM.

[Jikoo]

Thank you Zinthose,

It's interesting ! It works very well !

[Zinthose]

Thank you Zinthose,

It's interesting ! It works very well !

Thanks

[WeMartiansAreFriendly]

You have an interesting coding style, it is very readable.

[Zinthose]

You have an interesting coding style, it is very readable.

I'm humbled, but isn't that the point witting code? So the next guy, including yourself can make sence if it?

[WeMartiansAreFriendly]

I'm humbled, but isn't that the point witting code? So the next guy, including yourself can make sence if it?

In this case yes, but it's not very common; appropriate and descriptive comments is quite rare. Yes I know what a message box does, no I don't know what this dllstruct is used for.

[Digisoul]

I needed a way to HexEdit / Patch a file to repair a common file corruption problem is a software package my company uses. I first used the AutoIt core FileOpen/FileWrite functions but ran this method required me to open the whole file into memory. And the files I work with can be several hundred megabytes in size. After searching I came up with this solution.

I hope someone finds it useful

AutoIt        expandcollapse  popup

#include <WinAPI.au3>
#include <File.au3>
#include <String.au3>

_Demo()

Func _Demo()
    Local Const $TestFile_Path = @ScriptDir & "\Test.Bin"
    Local $TestFile_ID, $bData
    
    ;## Hex offsets / lengths of the data stored in the file.
        Local Const $Offset_Phone[2]        = [0x012,  4]
        Local Const $Offset_NewToy[2]       = [0x1b6, 18]
        Local Const $Offset_Recycle[2]      = [0x594, 24]

    ;## Binary string of the test file.
        Local Const $TestFile_Data = "0x" & _ 
            "42494E000000000000000000000000000000867530900000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000446F6E27742054617A65206D" & _
            "652042726F21000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000536F796C656E742067726565" & _
            "6E2069732070656F706C6521000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000" & _
            "000000000000000000000000"

    ;## Create Test File
        $TestFile_ID = FileOpen($TestFile_Path, 14)
        FileWrite($TestFile_ID, Binary($TestFile_Data))
        FileClose($TestFile_ID)
        
    ;## Read the Recycle Value
        $bData = _HexRead($TestFile_Path, $Offset_Recycle[0], $Offset_Recycle[1])
    
    ;## Convert data to a string and display.
        MsgBox(4096, Default, "Recycle:" & @CRLF & BinaryToString($bData))
    
    ;## Change the recycle value
        $bData = StringToBinary("It Tastes like chicken!!")
        _HexWrite($TestFile_Path, $Offset_Recycle[0], $bData)
    
    ;## Read the Recycle Value
        $bData = _HexRead($TestFile_Path, $Offset_Recycle[0], $Offset_Recycle[1])
    
    ;## Convert data to a string and display.
        MsgBox(4096, Default, "Recycle:" & @CRLF & BinaryToString($bData))  
    
EndFunc

#Region - HexEdit
    Func _HexWrite($FilePath, $Offset, $BinaryValue)
        Local $Buffer, $ptr, $bLen, $fLen, $hFile, $Result, $Written
        
        ;## Parameter Checks
            If Not FileExists($FilePath)    Then    Return SetError(1, @error, 0)
            $fLen = FileGetSize($FilePath)
            If $Offset > $fLen              Then    Return SetError(2, @error, 0)
            If Not IsBinary($BinaryValue)   Then    Return SetError(3, @error, 0)
            $bLen = BinaryLen($BinaryValue)
            If $bLen > $Offset + $fLen      Then    Return SetError(4, @error, 0)
        
        ;## Place the supplied binary value into a dll structure.
            $Buffer = DllStructCreate("byte[" & $bLen & "]")
        
            DllStructSetData($Buffer, 1, $BinaryValue)
            If @error Then Return SetError(5, @error, 0)
        
            $ptr = DllStructGetPtr($Buffer)
        
        ;## Open File
            $hFile = _WinAPI_CreateFile($FilePath, 2, 4, 0)
            If $hFile = 0 Then Return SetError(6, @error, 0)
        
        ;## Move file pointer to offset location
            $Result = _WinAPI_SetFilePointer($hFile, $Offset)
            $err = @error
            If $Result = 0xFFFFFFFF Then
                _WinAPI_CloseHandle($hFile)
                Return SetError(7, $err, 0)
            EndIf
            
        ;## Write new Value
            $Result = _WinAPI_WriteFile($hFile, $ptr, $bLen, $Written)
            $err = @error
            If Not $Result Then
                _WinAPI_CloseHandle($hFile)
                Return SetError(8, $err, 0)
            EndIf
        
        ;## Close File
            _WinAPI_CloseHandle($hFile)
            If Not $Result Then Return SetError(9, @error, 0)
    EndFunc

    Func _HexRead($FilePath, $Offset, $Length)
        Local $Buffer, $ptr, $fLen, $hFile, $Result, $Read, $err, $Pos
        
        ;## Parameter Checks
            If Not FileExists($FilePath)    Then    Return SetError(1, @error, 0)
            $fLen = FileGetSize($FilePath)
            If $Offset > $fLen              Then    Return SetError(2, @error, 0)
            If $fLen < $Offset + $Length    Then    Return SetError(3, @error, 0)

        ;## Define the dll structure to store the data.
            $Buffer = DllStructCreate("byte[" & $Length & "]")
            $ptr = DllStructGetPtr($Buffer)
        
        ;## Open File
            $hFile = _WinAPI_CreateFile($FilePath, 2, 2, 0)
            If $hFile = 0 Then Return SetError(5, @error, 0)
        
        ;## Move file pointer to offset location
            $Pos = $Offset
            $Result = _WinAPI_SetFilePointer($hFile, $Pos)
            $err = @error
            If $Result = 0xFFFFFFFF Then
                _WinAPI_CloseHandle($hFile)
                Return SetError(6, $err, 0)
            EndIf
            
        ;## Read from file
            $Read = 0
            $Result = _WinAPI_ReadFile($hFile, $ptr, $Length, $Read)
            $err = @error
            If Not $Result Then
                _WinAPI_CloseHandle($hFile)
                Return SetError(7, $err, 0)
            EndIf
        
        ;## Close File
            _WinAPI_CloseHandle($hFile)
            If Not $Result Then Return SetError(8, @error, 0)
            
        ;## Return Data
            $Result = DllStructGetData($Buffer, 1)
            
            Return $Result
    EndFunc

    Func _WinAPI_SetFilePointer($hFile, $nDistance, $nMethod = 0)
        Local $nRet
        $nRet = DllCall("kernel32.dll", "dword", "SetFilePointer", "ptr", $hFile, "long", $nDistance, "ptr", 0, "dword", $nMethod)
        
        return $nRet[0]
    EndFunc
#EndRegion

Your Script is Quite usefull can you tell me if i have some binary data but don't have its offset then how can i creat its offset ?

[Zinthose]

Your Script is Quite usefull can you tell me if i have some binary data but don't have its offset then how can i creat its offset ?

You will need to know your way around a hex editor and be prepared to perform some file comparisons before and after a change to identify were the file change hex offsets are.

Hex editing is more art than science IMO. You just need to get a free hex editor, backup your files, and work the proverbial clay until it just clicks. If you do a Google search you might find a hex editor tutorial.

Anyway, Teaching binary file manipulations are probably out of the scope of the AutoIt forums.

[Digisoul]

You will need to know your way around a hex editor and be prepared to perform some file comparisons before and after a change to identify were the file change hex offsets are.

Hex editing is more art than science IMO. You just need to get a free hex editor, backup your files, and work the proverbial clay until it just clicks. If you do a Google search you might find a hex editor tutorial.

Anyway, Teaching binary file manipulations are probably out of the scope of the AutoIt forums.

Wel i m using hackman 9 as hex editor. my quention is that is it possible to search any binary bytes if you don't know the offset, bcoz i want to search some bytes in random files. so i can't be sure about its offset.

[Zinthose]

Wel i m using hackman 9 as hex editor. my quention is that is it possible to search any binary bytes if you don't know the offset, bcoz i want to search some bytes in random files. so i can't be sure about its offset.

So you want an additional function to search a binary file and return the Offset if the value is found?

Func _HexSearch($FilePath, $BinaryValue, $StartOffset = Default)
    ;## Perform Magic
        Return Aberacadabera()
EndFunc

EDIT: I created the _HexSearch function and added it to the original post.

Edited by Zinthose, 21 November 2008 - 09:51 PM.

[Digisoul]

EDIT: I created the _HexSearch function and added it to the original post.

Awesome ! thats the thing i want. Thankx for this function.

[Jango]

You have an interesting coding style, it is very readable.

I agree, moreover it's really usefull (for me at least). Well done.

[karham]

Simply Awesome!

Hehehehe
Thnx a lot I've been needing something like it but i'm still learning so I couldnt make one like this one ;D

[goldenix]

it works, thanx, all i need now is to convert hex to text.

nvm:

$data = _HexRead('chai_4-3.zip.torrent', '369', '20') ; 20 is the lenght of the output

$data = StringTrimLeft($data,2)

$data = _HexToString($data)
ConsoleWrite($data & @CRLF)

Edited by goldenix, 30 August 2009 - 03:22 PM.

[Ashalshaikh]

WOW !!!!
Realy Good !!
I Was Need It !!
Thanks !!

[goldenix]

Question, Hex edit function does not work. What im doing wrong?

I have a file 50 4D 56 D2

Now I want to replace D2 With DE

I do this and nothing happens.

$result =  _HexWrite('sample.txt', 3, 'DE')

ConsoleWrite($result & @CRLF)

EDIT Never mind:

it works this way:

    $_HexRead   = _HexRead('autosave.pmv', 3, 2)
    ConsoleWrite($_HexRead & @CRLF)

    $result =  _HexWrite('Riddle.pmv', 3, $_HexRead)

Edited by goldenix, 29 November 2009 - 08:09 PM.

[BinaryBrother]

For other newbies like me... On the _HexRead(file,offset,length) function... To actually get the 'offset' rather than the pointer, convert the offset to dec before parsing it through that function...

_HexRead($File,Dec($Offset),$Length)

I'm a complete newbie with Hex stuff, so it took me a few mins to figure it out...

Edited by BinaryBrother, 05 January 2010 - 08:51 AM.