I need to know how to get the starting handle number list for the Win32Api function RegOpenKeyEx. I am trying to look at HKEY_LOCAL_MACHINE ..... and need the first parameter. I have an example I am using from Nigel Cotes mapi component but I am attempting to adapt this part of it to detect the existance of a particular PDF printer.

RegOpenKeyEx(-2147483647, "Software\Microsoft\Windows Messaging Subsystem\Profiles", 0, 0, @lnHandle)

The first parameter above is a number and I don't know what this is or how to modify it for my use to get to

HKEY_LOCAL_MACHINE\System\CurrentControlSet\control\Print\Printers\DocuCom PDF Driver


Where do I find help on WIN32API for these parameters. I tried the API section but could not find anything (probably because I have not learned to use it properly yet).

Thanks in advance

Terry