Newbie question regarding drives, second phase

ruby-talk
1

Chris,

I thanked you before for your help with this issue. I downloaded your
software and got my program to do what I wanted it to.

I’ve taken a step back from the problem, however, and maybe I was asking the
wrong question.

I’m writing to ask you for one more piece of help.

So, in order to ask it, let me explain. I’ve been using Flash as a frontend
for the simple Ruby programs I write – I already understand Flash and I
figure it’s best to understand as much as possible of what I’m doing, and
RubyTK and FXRuby both present problems for me in terms of understanding an
alien logic.

So Flash is fine, except that owing to its web antecedents there is no
built-in way to access the contents of a computer’s local drive(s). There’s
no simple method for calling up an Open dialog box like every reasonable GUI
language has.

I have these alternatives, I reason: I can create such a dialog in FLash
(hence my start with finding out what drives a computer has); I can include
Fox or TK and just use the part that calls the Open dialog box; I can call
it from Win32API.

In the long run, I expect I’ll benefit from completing variation 1. But in
order to learn Ruby and put my simple programs in a GUI I’m spending all my
time right now working in Flash’s version of Javascript, called
Actionscript. Being a very beginning programmer, I think I had better stick
to one language at a time.

My first efforts I actually went ahead and created with FXRuby; however,
these programs fail my principle of Understand What You Write. (One of the
reasons I like Ruby so much.)

So I am thinking that I should just use a blackbox approach to the issue of
getting an open dialog onscreen – use Flash for my GUI and stick in a line
that calls that dialog. I can put in the appropriate line for FXRuby that
will do that.

However, to my way of thinking, calling it directly from Windows would be
more efficient.

The half-hour or so I’ve perused the MSDN documentation about Windows gives
me the shudders (did I mention I come from a tech-writing background, and
that I use Ruby for string manipulations? In other words: an English major).

So, to my question: if I were to use Win32API to get an open dialog box, do
you know what the line should say?

Or: do you know where there are some examples that I could study and
imitate?

Or: do you have an idea the best way to figure this out or the best place to
ask?

Thanking you in advance for you guidance, and your patience with me as I
wobbled my way to asking for help.

Yours,

Roger Sperberg
roger.sperberg@aspenpubl.com

···

-----Original Message-----
From: Chris Morris [mailto:chrismo@clabs.org]
Sent: Wednesday, March 05, 2003 1:30 PM
To: ruby-talk@ruby-lang.org
Subject: Re: Newbie question regarding drives

IIRC, I don’t think there’s a handy cross-platform solution.

Here’s code from my clUtil lib to do this on Windows:

Copyright Chris Morris

BSD License. Full download and license available here:

http://clabs.org/scrpware.htm – look for

cLabs Ruby Utilities

module Windows
def Windows.drives(typeFilter=nil)
Drives::drives(typeFilter)
end

module Drives
GetDriveType = Win32API.new(“kernel32”, “GetDriveTypeA”,
[‘P’], ‘L’)
GetLogicalDriveStrings = Win32API.new(“kernel32”,
“GetLogicalDriveStrings”, [‘L’, ‘P’], ‘L’)

DRIVE_UNKNOWN      = 0 # The drive type cannot be determined.
DRIVE_NO_ROOT_DIR  = 1 # The root path is invalid. For example, no

volume is mounted at the path.
DRIVE_REMOVABLE = 2 # The disk can be removed from the drive.
DRIVE_FIXED = 3 # The disk cannot be removed from
the drive.
DRIVE_REMOTE = 4 # The drive is a remote (network) drive.
DRIVE_CDROM = 5 # The drive is a CD-ROM drive.
DRIVE_RAMDISK = 6 # The drive is a RAM disk.
DriveTypes = {
DRIVE_UNKNOWN => ‘Unknown’,
DRIVE_NO_ROOT_DIR => ‘Invalid’,
DRIVE_REMOVABLE => ‘Removable/Floppy’,
DRIVE_FIXED => ‘Fixed’,
DRIVE_REMOTE => ‘Network’,
DRIVE_CDROM => ‘CD’,
DRIVE_RAMDISK => ‘RAM’
}

Drive = Struct.new('Drive', :name, :type, :typedesc)

def Drives.drives(typeFilter=nil)
  driveNames = ' ' * 255
  GetLogicalDriveStrings.Call(255, driveNames)
  driveNames.strip!
  driveNames = driveNames.split("\000")
  drivesAry = []
  driveNames.each do |drv|
    type = GetDriveType.Call(drv)
    if (!typeFilter) || (type == typeFilter)
      drive = Drive.new(drv, type, DriveTypes[type])
      drivesAry << drive
    end
  end
  drivesAry
end

end
end

----- Original Message -----
From: “Sperberg, Roger” roger.sperberg@aspenpublishers.com
To: “ruby-talk ML” ruby-talk@ruby-lang.org
Sent: Wednesday, March 05, 2003 12:22 PM
Subject: Newbie question regarding drives

Can someone advise me of how to find out within my Ruby program what
drives
are on a system, and what type of drive (local hard drive,
floppy, CD-ROM,
etc.) they are?

I’m working with a Win2000 system, but it might also be
used by someone
running Linux.

TIA,

Roger Sperberg

2

However, to my way of thinking, calling it directly from Windows would be
more efficient.

More efficient for the machine (though not noticeably), terribly inefficient
for you :slight_smile: The Windows API is pretty low-level. I do little directly with
the API if I can help it. Everyone uses libraries that sit on top of the
API – C++ has MFC, Delphi has the VCL, VB is, well, VB, Java uses the
Virtual Machine for Windows which handles all the API talking, etc etc.

Back to your problem – will your Flash be served from a web server, or
somehow run locally? Also, what sort of access do you need to the client
drive? If you’re coming from a web server, you will have very definite
limitations of what client-side things you can access. There is one caveat I
know of, and that is a certain CGI form element that should kick open a
dialog for the user to select a file for uploading to the server, or some
such – I’m a bit hazy on that.

Chris