DispatchSetInformation Routines
A driver's DispatchSetInformation routine handles IRPs for the IRP_MJ_SET_INFORMATION I/O function code. Driver support for this I/O function code is optional, and typically appears in higher-level or file system drivers. This request is sent by the I/O manager and other operating system components, as well as other kernel-mode drivers. For example, it is sent when a user-mode application calls SetEndOfFile, and when a kernel-mode component calls ZwSetInformationFile.