MemoryMappedFile Class Reference

Maps a file into virtual memory for easy reading and/or writing. More...

List of all members.

Public Types
enum	AccessMode { readOnly, readWrite }
	The read/write flags used when opening a memory mapped file. More...
Public Member Functions
	MemoryMappedFile (const File &file, AccessMode mode)
	Opens a file and maps it to an area of virtual memory.
	~MemoryMappedFile ()
	Destructor.
void *	getData () const noexcept
	Returns the address at which this file has been mapped, or a null pointer if the file couldn't be successfully mapped.
size_t	getSize () const noexcept
	Returns the number of bytes of data that are available for reading or writing.

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Detailed Description

Maps a file into virtual memory for easy reading and/or writing.

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Member Enumeration Documentation

enum MemoryMappedFile::AccessMode

The read/write flags used when opening a memory mapped file.

Enumerator:

readOnly	Indicates that the memory can only be read.
readWrite	Indicates that the memory can be read and written to - changes that are made will be flushed back to disk at the whim of the OS.

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Constructor & Destructor Documentation

MemoryMappedFile::MemoryMappedFile	(	const File &	file,
		AccessMode	mode
	)

Opens a file and maps it to an area of virtual memory.

The file should already exist, and should already be the size that you want to work with when you call this. If the file is resized after being opened, the behaviour is undefined.

If the file exists and the operation succeeds, the getData() and getSize() methods will return the location and size of the data that can be read or written. Note that the entire file is not read into memory immediately - the OS simply creates a virtual mapping, which will lazily pull the data into memory when blocks are accessed.

If the file can't be opened for some reason, the getData() method will return a null pointer.

MemoryMappedFile::~MemoryMappedFile

(

)

Destructor.

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Member Function Documentation

void* MemoryMappedFile::getData

(

)

const

Returns the address at which this file has been mapped, or a null pointer if the file couldn't be successfully mapped.

size_t MemoryMappedFile::getSize

(

)

const

Returns the number of bytes of data that are available for reading or writing.

This will normally be the size of the file.

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The documentation for this class was generated from the following file:

• juce_MemoryMappedFile.h