From: Bill Kelly <billk@...>
Date: 2003-07-26T08:15:28+09:00
Subject: Re: Quick way to find all drives in a windows box

Hi,

From: "Damphyr" <damphyr@freemail.gr>
>
> Does anyone have a quick and elegant :) way to find all available drive 
> letters on a windows box?
> I'm thinking in terms of Java File.listRoots() functionality.

Here's one way:

# define the call:
>> require 'Win32API'
=> true
>> GetLogicalDriveStrings = Win32API.new("kernel32", "GetLogicalDriveStrings", ['L', 'P'], 'L')
=> #<Win32API:0x2ab0968>

# create a buffer to hold the result and execute the call:
>> buf = "\0" * 1024
>> len = GetLogicalDriveStrings.call(buf.length, buf)
=> 40
# if successful, <len> is now the length of the null-terminated
# drive names appended into the buffer.... (if failed, <len> will
# be zero, or some size exceeding the length we passed in)

# looking at the raw data...
>> buf[0..len]
=> "A:\\\000C:\\\000D:\\\000E:\\\000F:\\\000G:\\\000M:\\\000P:\\\000T:\\\000Z:\\\000\000"

# split drive strings into array:
>> buf[0..len].split("\0")
=> ["A:\\", "C:\\", "D:\\", "E:\\", "F:\\", "G:\\", "M:\\", "P:\\", "T:\\", "Z:\\"]


Hope this helps,

Bill