JCL Help:NtfsZeroDataByHandle

 JCL Help: NtfsZeroDataByHandle Function

FilesandIO.FileSystems.NTFS

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Summary

Decommits storage for a specified range within a sparse file.

Pascal

 function NtfsZeroDataByHandle(const Handle: THandle; const First: Int64; const Last: Int64): Boolean;

Parameters

Parameters	Description
const Handle: THandle	Identifies the file for which you want to zero a range.
const First: Int64	Indicates the file offset, in bytes, of the start of the range to set to zeroes.
const Last: Int64	Indicates the byte offset of the first byte beyond the last zeroed byte.

Return Value

If the function succeeds it returns True, otherwise it returns False.

Description

NtfsZeroDataByHandle tells the NTFS filesystem to 'zero' the data in the specified range for the file identified by Handle. This in effect decommits storage for the specified range. That is, the specified range no longer occupies storage space. Subsequently reading a byte in this range will return 0. The range will remain uncommitted until you write to it again.

See Also

NtfsZeroDataByName

About

Unit

JclNTFS

Donator

Marcel van Brakel

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