CallbackDisk™

CallbackDisk is a component for software developers lets you create virtual drives and disks, format them to FAT or NTFS, and mount as if they were physical devices.

Virtual disk is the one that has a file system on it, but is not physically located on a disk partition. The storage can be actually located in a file residing on a local disk, or in applicaiton resources, or in memory, or somewhere at a remote location. The important part is that this disk is visible to the user (and to other applications) as if it were a formatted hard disk partition.

Virual disk can be needed in many cases. The examples of use are:

• the application stores some data internally (in resources or in supplementary files) and it needs to use some library, which can only work with file located within a system-wide file system. The examples include DirectX libraries, Flash player, many third-party components.
• the application must hide presence of the disk from the user, while keeping it (the disk) available for some applications
• creation of encrypted virtual disks
• memory-stored virtual disks which are disposed of after application shutdown
• creation of shapshots which can be rolled back or flushed to the actual disk
• and more ...

In modern operating systems like Windows, Unix / Linux or Windows Mobile, to create a virtual disk from the application one must develop a kernel-mode driver. Development of such driver is a complicated task that requires deep knowledge of the operating system internals. Besides complexity, driver development is a very time-consuming process.

To solve these problems we offer CallbackDisk component (a library for software development). The product includes ready-to-deploy kernel-mode device driver and a user-mode API, which is used by your application. The driver creates a virtual disk (you can format this disk to FAT or NTFS) and provide system-wide access to the disk. The API lets you manage the driver and the virtual disk from any Windows or .NET application.
CallbackDisk is based on the same device driver as Solid File System Driver Edition SDK and includes only the basic functionality, necessary to implement a virtual disk. If you want to use advanced features, that the drivers can provide (such as access control, encyrption, resizeable storage, advanced functions of SolFS itself), take a look at Solid File System Driver Edition SDK.

CallbackDisk lets you create a virtual disk device. If you need to expose the files to the operating system, i.e. create your own file system, then you need to take a look at our Callback File System product. Callback File System lets you create virtual file systems and disks and make them visible them to the system as if they were physical devices with a standard file system.

For technical information about CallbackDisk SDK please read Detailed Description.

Read about the differences between various Virtual Storage products by EldoS Corporation.