System.IO.MemoryMappedFiles.MemoryMappedFile.CreateFromFile Method

Creates a memory-mapped file that has the specified name, capacity, access type, security permissions, inheritability, and disposal requirement from a file on disk.

Syntax

[System.MonoLimitation("memoryMappedFileSecurity is currently ignored")]
public static MemoryMappedFile CreateFromFile (System.IO.FileStream fileStream, string mapName, long capacity, MemoryMappedFileAccess access, MemoryMappedFileSecurity memoryMappedFileSecurity, System.IO.HandleInheritability inheritability, bool leaveOpen)

Parameters

fileStream
The fileStream to the file to map.
mapName
A name to assign to the memory-mapped file.
capacity
The maximum size, in bytes, to allocate to the memory-mapped file. Specify 0 to set the capacity to the size of the file on disk.
access
One of the enumeration values that specifies the type of access allowed to the memory-mapped file. The default is MemoryMappedFileAccess.ReadWrite.
memoryMappedFileSecurity
The permissions that can be granted for file access and operations on memory-mapped files.
inheritability
One of the enumeration values that specifies whether a handle to the memory-mapped file can be inherited by a child process. The default is System.IO.HandleInheritability.None.
leaveOpen
true to not dispose fileStream after the System.IO.MemoryMappedFiles.MemoryMappedFile is closed; false to dispose fileStream.

Returns

A memory-mapped file that has the specified characteristics.

Remarks

If capacity is larger than the size of the file on disk, the file on disk is increased to match the specified capacity even if no data is written to the memory-mapped file. To prevent this from occurring, specify 0 (zero) for the default capacity, which will internally set capacity to the size of the file on disk.

Requirements

Namespace: System.IO.MemoryMappedFiles
Assembly: System.Core (in System.Core.dll)
Assembly Versions: 4.0.0.0