Function Ptr

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Fabian.

currently running code is protected to prevent virus etc from causing problems.

however you can still access it:

Strict
Framework brl.blitz

'here we create a new bit of code in a temporary memory area:
Local PrepareArea:Byte Ptr = MemAlloc ( 7 )
PrepareArea [ 0 ] = 184 'mov eax,_RedirectFunc
( Byte Ptr Ptr ( PrepareArea + 1 ) ) [ 0 ] = RedirectFunc
PrepareArea [ 5 ] = 255 'jmp eax (part 1)
PrepareArea [ 6 ] = 224 'jmp eax (part 2)

'now we want to copy our new created function to the executable memory
'it should replace the String.FromWString function:
'MemCopy String.FromWString , PrepareArea , 7 'doesn't work, use this instead:
WriteProcessMemory GetCurrentProcess ( ) , String.FromWString , PrepareArea , 7 , Null 'works

'now let's just try to call String.FromWString and see what happens instead:
WriteStdout String.FromWString ( "Hello".ToWString ( ) ) + "~n"

Function RedirectFunc$ ( Param:Short Ptr )
  WriteStdout "Someone tried to call String.FromWString!~n"
  WriteStdout "String.FromWString was called with the following pointer as parameter:~n"
  WriteStdout Int Param + "~n"
  Return "This is the return value...."
EndFunction

Extern "Win32"
  Function GetCurrentProcess ( )
  Function WriteProcessMemory ( DstProc , Dst:Byte Ptr , Src:Byte Ptr , Size , Written Ptr )
EndExtern

This protection isn't valid for the OS, since api functions belong to the os you can use them to access this memory.