Get registry string from ruby 2.0

[Al Hart]

There are a lot of threads about this, but I am getting confused.

I took a look at Win32Api.rb in SketchUp 2014, and it says:

"Win32API is deprecated after Ruby 1.9.1; use dl directly instead"

Do I took a look at DL, and it says:

"DL is deprecated, please use Fiddle"

So I took a look at Fiddle, which does have some Win32 stuff, but I couldn't find an example on how to get a string from the registry using Fiddle.

Can someone post, or point me to a Ruby 2.0 example which will run in SketchUp and read a Windows Registry String?

[Dan Rathbun]

The standard library has a Registry class BUT it is currently bugged with regard to string encodings.

If you wish to be backward compatible you can still use the Win32API class, which in Ruby 1.9.1+, becomes a wrapper to the DL class (which is more C-like,) which in Ruby 2.x, becomes a wrapper to Fiddle.

There should be examples in the CHM or embedded in the ruby scripts that load them (the CHM help docs are generated from inline documentation.)

[Dan Rathbun]

If you wish to do this from a C/C++ extension, you can:

include "Winreg.h" (include "Windows.h"),
load the "Advapi32.dll" library,
and use the registry functions.

The pages on individual functions have examples.

http://msdn.microsoft.com/en-us/library/ms724875(v=VS.85).aspx

These are the functions you'd call using DL, Win32API or Fiddle if you go that route.

Add: These ways are more complicated, as you must first open a handle to the registry key before a calling read, and be sure to call close on the key when done (like in an ensure clause! )

[Al Hart]

Thanks Dan, this looks great.

Let me try it out

[Al Hart]

Thanks Dan - that works!

Is there anything similar for Ruby 1.8, or do I need to continue to use Win32API.so to read the registry?

[Dan Rathbun]

@al hart said:

Thanks Dan - that works!

Is there anything similar for Ruby 1.8, or do I need to continue to use Win32API.so to read the registry?

WHAT works ?

(I talked about at least 3 ways.)

IF you went with the low level system calls, via Win32API class then you use the "Win32API.rb" wrapper script that comes with Ruby 1.9.x and higher.

As I said, ... for Ruby 1.8.6, you use the "Win32API.so" (and/or "win32ole.so",) files ("lifted from the Windows Installer package",) that I posted in the "Plugins" forum. (Use the Author Index Sticky post to find it.)

[Dan Rathbun]

You can ALSO instead use the WIN32OLE class ("win32ole.rb" all lowercase,) and instantiate a ref to a Windows Scripting Host object, which has SAFE functions to access the registry.
http://msdn.microsoft.com/en-us/library/x05fawxd(v=vs.84).aspx

Something like this (tested):

module MyCode

  def self.sketchup_install_location()

    require "win32ole"

    wsh = WIN32OLE.new("WScript.Shell")
    begin
      val = wsh.RegRead("HKLM\\Software\\Wow6432Node\\SketchUp\\SketchUp 2014\\InstallLocation\\")
    rescue WIN32OLERuntimeError
      val = wsh.RegRead("HKLM\\Software\\SketchUp\\SketchUp 2014\\InstallLocation\\")
    end

    wsh.ole_free

    return val

  end

end

Add: The value returned (in my test.) is "UTF-8" encoded, which is a good thing.

FYI: The path to the key for SketchUp < 2013 is under:
"HKLM\Software\Google\Google SketchUp 8\InstallLocation\"
etc. for older versions.
But "win32ole.so" does not come with older version of SketchUp. You will need to provide a 1.8.6 compiled versions of the so file. [url=http://sketchucation.com/forums/viewtopic.php?t=42732:27osqac0]It is posted (by me,) in the "Plugins" forum[/url:27osqac0].

[Al Hart]

@dan rathbun said:

@al hart said:

Thanks Dan - that works!

WHAT works ?

(I talked about at least 3 ways.)

We wound up using win32ole and RegRead

However we ran into problems with an uncaught exception when the Registry Key we passed did not exist, so we added a second rescue for the second registry key.

Like this (I added XX to the key to intentionally make it fail)

require "win32ole"

wsh = WIN32OLE.new("WScript.Shell")
begin
	val = wsh.RegRead("HKLM\\Software\\Wow6432Node\\SketchUpXX\\SketchUp 2014\\InstallLocation\\")
rescue WIN32OLERuntimeError
	val = ""
end#begin/rescue

if (val == "")
	begin
		val = wsh.RegRead("HKLM\\Software\\SketchUpXX\\SketchUp 2014\\InstallLocation\\")
	rescue WIN32OLERuntimeError
		val = ""
	end#begin/rescue
end#if

wsh.ole_free

puts "VAL; " + val