Virtual Disk API Programming Guide - Documentation - VMware

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Virtual Disk API Functions 4
This chapter provides an overview of functions in the Virtual Disk API and includes the following sections:
“Virtual Disk Library Functions” on page 27
“Start Up” on page 28
“Disk Operations” on page 30
“Error Handling” on page 31
“Metadata Handling” on page 31
“Cloning a Virtual Disk” on page 31
“Disk Chaining and Redo Logs” on page 32
“Administrative Disk Operations” on page 33
“Shut Down” on page 35
“Advanced Transport APIs” on page 35
“Updating Applications for Advanced Transport” on page 39
“Multithreading Considerations” on page 41
“Capabilities of Library Calls” on page 41
After a presentation of Virtual Disk API functions in alphabetic order, sections focus on what the functions do,
in the normal order they would appear in a program, except advanced transport functions (SAN and HotAdd)
appear after the shutdown functions.
Virtual Disk Library Functions
You can find the VixDiskLib API Reference by using a Web browser to open the doc/index.html file in the
VDDK software distribution. As in most reference manuals, functions are organized alphabetically, whereas
in this chapter, functions are ordered by how they might be called.
When the API reference says that a function supports “only hosted disks,” it means virtual disk images hosted
by VMware Workstation or similar products. Virtual disk stored on VMFS partitions managed by ESX/ESXi or
vCenter Server is called “managed disk.”
The functions described in this chapter are based on concepts and employ data structures documented in
Chapter 3, “Virtual Disk Interfaces,” on page 19.
If the library accesses virtual disk on VMFS, I/O by default goes through the ESX/ESXi host, which manages
physical disk storage. To use function calls that provide direct access to SAN storage, start your program by
calling the VixDiskLib_ConnectEx() function, as described in “Advanced Transport APIs” on page 35.
VMware, Inc. 27