I'm looking to do some things involving (removable) devices, so I was looking at WMI and other APIs, the 'Devices and Printers' screen and the Safely Remove Hardware popup as I want to have as seamless an experience as possible. Problem however.. is that I can't find any way to get the names as my user 'knows' them in his PC.
Example... I connect an iPod, this shows in both DaP and SRH as 'iPod', which is awesome. In WMI the closest I've been able to find are 'Apple Inc. iPod' and 'Apple iPod USB Device'. Similar stories apply for other hardware like a WD My Book and other such hardware. Where do I find the proper string?
Since I am beginning to doubt whether I'm approaching the bigger picture from the right direction with WMI, a bit more explanation... we do a fair bit with removable hardware around here, 99% disk drives. I thought over hard-coding a loop from A to Z and inspect each drive, but to my knowledge removable volumes do not NEED to be mounted on a letter, but can also be dumped in an empty folder on ntfs. That and my small doubt there might be other (non-drive) hardware that needs 'finalizing' before being unplugged is adding to a small nagging doubt that I might be asking the wrong question alltogether. (editors: if this is too much irrelevant information, feel free to edit this out of the question.)
You can get this with WMI. This Powershell script does just that, the interesting property being Label:
PS C:\>gwmi -Class Win32_Volume | select Name, Label
Name Label
---- -----
C:\ Windows 7
D:\ Windows 2008
C:\TEST\ MYUSBKEY
E:\ RECOVERY
As you can see, it also works with devices not mounted with a letter.
As far as i can see, this does not work. The Powershell code (which is nothing else than another wmi wrapper) only retrieves the volume information for the mounted devices, such as usb keys. I have an iphone connected, and i see noting..
Related
My Mac's hard drive failed and I had a replacement drive installed. All R related programs were installed as if my computer was brand new.
Prior to the failure, if I inserted a graphic into a RMardown document, the rendered size of the graphic was consistent and directly related to the actual size of the screen shot image.
Now, relatively small screen captures render large in size. I attempt to add a pic to show the problem. Not certain what I need to do to fix this situation. This is a book that will soon go to publication. As is stands, the publication is delayed unless I am able to somehow return to 'normal.' A Time Machine restore is out of the question for reasons I cannot go into, even though that was attempted. Several Apple senior advisors with whom I spoke do not recommend the 'Time Machine' restore option. As such, I seek another solution - hopefully not individually resizing 1,200+ text images. pic of mis-sizing
I hope this makes sense, I am not sure how exactly I should word this...
Hi, I am trying to write a program that will be able to monitor the audio output of certain processes. I am having a hell of a time finding a way to actually do this. I have only been able to find ways to get the current volume level, but not the actual output level. I've been searching through Stackoverflow, but everything I've found is only able to fetch the program's volume control level (like the slider in the Windows Volume mixer, however I am basically looking to get the value of the fluctuating green bar in the mixer)
I basically want to check the output level of a program every x milliseconds and if it is above a certain threshold, run a method to do something. How can I do this?
Thanks!
Quick edit to be clear: Win 7+ with C++
You probably want IAudioPeakMeter
This sample app here looks promising.
I’m using QDir::drives() to get the list of drives. It works great on Windows, but on Linux and Mac it only returns a single item “/”, i. e. root. It is expected behavior, but how can I get a list of drives on Mac and Linux?
Non-Qt, native API solutions are also welcome.
Clarification on "drive" definition: I'd like to get a list of mount points that are visble as "drives" in Finder or Linux built-in file manager.
As far as the filesystem is concerned, there is no concept of drives in Unix/Linux (I can't vouch for MacOSX but I'd say it's the same). The closest thing would probably be mount points, but a normal application shouldn't bother about them since all is already available under the filesystem root / (hence the behaviour of QDir::drives() that you observe).
If you really want to see which mount points are in use, you could parse the output of the mount command (without any arguments) or, at least on Linux, the contents of the /etc/mtab file. Beware though, mount points can get pretty hairy real quick (loop devices, FUSE filesystems, network shares, ...) so, again, I wouldn't recommend making use of them unless your application is designed to administer them.
Keep in mind that on Unix-y OSes, mount points are normally a matter for system administrators, not end-users, unless we're speaking of removable media or transient network shares.
Edit: Following your clarifications in the comments, on Linux you should use getmntent or getmntent_r to parse the contents of the /etc/mtab file and thus get a list of all mount points and the corresponding devices.
The trick after that is to determine which ones you want to display (removable? network share?). I know that /sys/block/... can help with that, but I don't know all the details so you'll have to dig a bit more.
For example, to check whether /dev/sdd1 (a USB key) mounted on /media/usb0/ is a removable device, you could do (note how I use the device name sdd, not the partition name sdd1):
$ cat /sys/block/sdd/removable
1
As opposed to my main hard drive:
$ cat /sys/block/sda/removable
0
Hope this puts you on the right track.
For OS X, the Disk Arbitration framework can be used to list and monitor drives and mount points
Scraping the output of mount shell command is certainly one option on either platform - although, what is your definition of a drive here? Physical media, removable drivers, network volumes? You'll need to do a lot of filtering.
On MacOSX, the mount point for removable media, network volumes, and secondary hard-drives is always under /Volumes/, so simply enumerating items in this directory will do the trick if your definition of a drive is broad. This ought to be fairly safe as they're all automounted .
On Linux, there are a variety of locations depending on the particular distro in use. /mnt/ is the traditional, but there are others.
In linux, the way to get information about drives currently mounted is to parse the mtab file. glibc provides a macro _PATH_MNTTAB to locate this file. See http://www.gnu.org/software/libc/manual/html_node/Mount-Information.html#Mount-Information
If you know the format of the drive/drives in question, you can use the df command to output the list of drives from the console or programatically as a system command. For example, to find all the ext4 drives:
df -t ext4
You can simply add additional formats onto the same command if you are interested in more than one type:
df -t ext4 -t tmpfs
This is going to return to you the physical location of the drive, the amount of memory it has, the amount of memory used, the amount of memory free, the use% and where it is mounted on the filesystem.
df will show you all of the drives mounted on the system, but some are going to be things that aren't really what you are looking for like temporary file systems, etc.
Not sure if this will work on OSX or not, but it does work on my Ubuntu 12.04 distribution.
Another way is to check for "Volumes"
df -H | grep "/Volumes"
I know that this is old, but it failed to mention getfsstat which I ended up using in macos. You can get a list of mounts (which will include most disks) using getfsstat. See man 2 getfsstat for further information.
Does anyone know how to be able to list down all the working local drives ( like drive C, D, removable disks and so on..) through combo box? And with that, I could be able to scan that specific drive and retrieve all the deleted files in it. I mean, to recover those files that have been deleted through formatting or by pressing shift+delete.
Just the functions that would be needed to do all of these stuffs would be enough though. By the way,
I know it would be hard if I would be using high-level language like Java and C# to do that, so visual c++ is the one I've been working on.
That's it! I hope to get positive response from you guys. Any suggestions would be highly appreciated. Thank you!
Use TestDrive
http://www.cgsecurity.org/wiki/TestDisk_Download
Its open source and works great
pull the drive out of the unit, if it's NTFS, go get getdataback for NTFS.
Install it on a windows computer, slave this drive to the system and scan it for deleted files.
It will show all the ntfs structures, even deleted or destroyed ones.
It's not free but will be the best $100 you ever spent if it saves your files.
Goal
I'm porting a filesystem to Windows, and am writing a more Windows-like interface for the mounter executable. Part of this process is letting the user locate a partition and pick a drive letter. Ultimately the choice of partition has to result in something I can open using CreateFile(), open(), fopen() or similar.
Leads
Windows seems to revolve around the concept of volumes, which don't seem quite analogous to disks, and only occur for already mounted filesystems.
Promising leads I've had include:
IOCTL_DISK_GET_DRIVE_LAYOUT_EX
Physical Disks and Volumes
Displaying Volume Paths
However these all end in volumes or offsets thereof, not the /dev/sda1 partition-specific-style handle I'm after.
This question is after a very similar thing, I considered a bounty until I observed the OP is after physical disk names, not partitions. This answer contains a method to brute force partition names, I'd like to avoid that (or see documentation containing bounds for the possible paths).
Question
I'd like:
Correct terminology and documentation for unmounted partitions in Windows.
An effective and documented method to reliably retrieve all available partitions.
The closest fit to the partition file abstraction as available in Linux, wherein all IO is bound to the appropriate area of the disk for the partition opened.
Update0
While the main goal is still opening raw partitions, it appears the solution may involve first acquiring a handle to each disk drive, and then using that in turn to acquire each partition. How to enumerate all the disk drives (even those without mounted volumes on them already) is required.
As you noted, you can use IOCTL_DISK_GET_DRIVE_LAYOUT_EX to get a list of partitions.
There's a good overview of the related concepts here. I wonder if the missing link for you is
Detecting the Type of Disk
There is no specific function to
programmatically detect the type of
disk a particular file or directory is
located on. There is an indirect
method.
First, call GetVolumePathName. Then,
call CreateFile to open the volume
using the path. Next, use
IOCTL_VOLUME_GET_VOLUME_DISK_EXTENTS
with the volume handle to obtain the
disk number and use the disk number to
construct the disk path, such as
"\?\PhysicalDriveX". Finally, use
IOCTL_DISK_GET_DRIVE_LAYOUT_EX to
obtain the partition list, and check
the PartitionType for each entry in
the partition list.
The full list of disk management control codes may have more that would be useful. To be honest I'm not sure how the Unix partition name maps onto Windows, maybe it just doesn't directly.
If you can imagine moving from safe haven of userspace and the Windows API (win32) to coding a device driver with NTTDK, you could try IoReadPartitionTableEx or some other low level disk function.
To be blunt, the best way to reliably get all mounted/unmounted disk partitions is to parse the mbr/gpt yourself.
First to clear a few things up: Disks contain partitions and partitions combine to create volumes. Therefore, you can have one volume which consists of two partitions from two different disks.
IOCTL_DISK_GET_DRIVE_LAYOUT_EX is the closest solution you're going to get without doing it manually. The problem with this is that it relies on windows which can incorrectly parse the MBR for god knows what reason. My current working theory is that if Windows was installed via EFI but is being booted via MBR, youll see this sort of issue. Windows manages to get away with this because most partition managers copy the important partition information to the MBR alongside the GPT. But this means that you wont get important information like the partition UUID (which is only stored in the GPT).
All of the other solutions involve getting the Volume information which is completely different from the partition information.
Side Note: a Volume id will usually be of the form \\.\Volume{PARTITION_UUID}. Cases where this would not hold: if the drive is partitioned with MBR and not GPT (MBR does not have a partition UUID, therefore windows makes one up), if you have a raid drive, or if you have a volume consisting of partitions from multiple disks (kinda the same thing as raid). Those are just the cases that come to my mind, dont hold me to them.
I think you're slightly mistaken in an earlier phase. For instance, you seem to assume that "mounting" works in Windows like it works in Unix. It's a bit different.
Let's start at the most familiar end. Paths like C:\ use drive letters. Those are essentially just a set of symbolic links nowadays (On Windows, they're more formally known as "junctions"). There's a base set for all users, and each user can add their own. Even if there is no drive letter for a volume, there will still be a volume name like \\?\Volume{4c1b02c1-d990-11dc-99ae-806e6f6e6963}\. You can use this volume name in calls to CreateFile() etc. I'm not sure if fopen() likes them, though.
The function QueryDosDevice will get you the Windows device name for a drive letter or a volume name. A device name looks like "\Device\HarddiskVolume1", but you can't pass it to CreateFile
Microsoft has example code to enumerate all partitions.
On Windows, like on Linux, you can open the partition itself as if it were a file. This is quite well documented under CreateFile.