MAKLogger::DtLargeFileFunctions Class Reference

Provides an interface for large (64bit) File IO. More...

List of all members.

Static Public Member Functions
static DtFileDesc	openForReading (const DtFilename &filename)
	Open a file for reading.
static DtFileDesc	openForWriting (const DtFilename &filename, bool truncate=true)
	Open a file for writing.
static DtFileDesc	openForReadingAndWriting (DtFilename filename, bool truncate=false)
	Open a file for reading and writing.
static bool	close (DtFileDesc)
	Closes the file.
static DtInt64	size (DtFileDesc)
	Gets the size of the file in bytes.
static DtInt64	tell (DtFileDesc)
	Get the current position in the file.
static DtInt64	seekCurrent (DtFileDesc, DtInt64)
	Set the current position relative to it's current position.
static DtInt64	seekEnd (DtFileDesc, DtInt64)
	Set the current position relative to the end of the file.
static DtInt64	seekSet (DtFileDesc, DtInt64)
	Set the current position relative to the beginning of the file.
static size_t	read (DtFileDesc, void *buffer, size_t bytesToRead)
	Read data from the file into the supplied buffer.
template<typename T >
static bool	readStruct (DtFileDesc fd, T &structObject)
	Read a structure from the file.
static char *	readBytes (DtFileDesc, size_t bytesToRead, size_t &totalBytesRead)
	Read data into a newly created buffer.
static size_t	write (DtFileDesc, const void *buffer, size_t bytesToWrite)
	Write the data from the buffer into the file.
template<typename T >
static bool	writeStruct (DtFileDesc fd, const T &structObject)
	Write a structure to the file.

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Detailed Description

Provides an interface for large (64bit) File IO.

Warning:

For all functions that can fail, use errno an perror to get reason.

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Member Function Documentation

static bool MAKLogger::DtLargeFileFunctions::close

(

DtFileDesc

)

[static]

Closes the file.

Return values:

true	The close succeeded.
false	The close failed.

static DtFileDesc MAKLogger::DtLargeFileFunctions::openForReading

(

const DtFilename &

filename

)

[static]

Open a file for reading.

Returns:

Returns a file description.

Return values:

0	Unable to open file for reading.

static DtFileDesc MAKLogger::DtLargeFileFunctions::openForReadingAndWriting	(	DtFilename	filename,
		bool	truncate = false
	)		[static]

Open a file for reading and writing.

Returns:

Returns a file description.

Return values:

0	Unable to open file for reading and writing.

static DtFileDesc MAKLogger::DtLargeFileFunctions::openForWriting	(	const DtFilename &	filename,
		bool	truncate = true
	)		[static]

Open a file for writing.

Returns:

Returns a valid file description.

Return values:

0	Unable to open file for writing.

static size_t MAKLogger::DtLargeFileFunctions::read	(	DtFileDesc	,
		void *	buffer,
		size_t	bytesToRead
	)		[static]

Read data from the file into the supplied buffer.

Returns:

Returns the number of bytes actually read.

Warning:

This function is dangerous since buffer may not be large enough. Use readBytes for safer access. Also if the file was not opened to support reading this call will return zero.

Referenced by readStruct().

static char* MAKLogger::DtLargeFileFunctions::readBytes	(	DtFileDesc	,
		size_t	bytesToRead,
		size_t &	totalBytesRead
	)		[static]

Read data into a newly created buffer.

Returns:

Returns a pointer to the data. This data will be allocated on the heap.

Return values:

NULL	If the file does not support reading.

Warning:

The buffer will contain undefined data after totalBytesRead bytes into the buffer if totalBytesRead != bytesToRead.

template<typename T >

static bool MAKLogger::DtLargeFileFunctions::readStruct	(	DtFileDesc	fd,
		T &	structObject
	)		[inline, static]

Read a structure from the file.

This function assumes the file data maps directly into the structure. This function will also work with built-in types.

Returns:

Whether the read was successful.

Warning:

If the read is not successful the object may not be in a complete state.

References read().

static DtInt64 MAKLogger::DtLargeFileFunctions::seekCurrent	(	DtFileDesc	,
		DtInt64
	)		[static]

Set the current position relative to it's current position.

Returns:

Returns the position in the file relative to beginning.

static DtInt64 MAKLogger::DtLargeFileFunctions::seekEnd	(	DtFileDesc	,
		DtInt64
	)		[static]

Set the current position relative to the end of the file.

Returns:

Returns the position in the file relative to beginning.

static DtInt64 MAKLogger::DtLargeFileFunctions::seekSet	(	DtFileDesc	,
		DtInt64
	)		[static]

Set the current position relative to the beginning of the file.

Returns:

Returns the position in the file relative to beginning.

static size_t MAKLogger::DtLargeFileFunctions::write	(	DtFileDesc	,
		const void *	buffer,
		size_t	bytesToWrite
	)		[static]

Write the data from the buffer into the file.

Returns:

Returns the number of bytes written.

Warning:

This function is dangerous since buffer may not be bytesToWrite.

Referenced by writeStruct().

template<typename T >

static bool MAKLogger::DtLargeFileFunctions::writeStruct	(	DtFileDesc	fd,
		const T &	structObject
	)		[inline, static]

Write a structure to the file.

This function assumes the file data maps directly into the structure. This function will also work with built-in types.

Warning:

If the read is not successful the file may not be in a valid state. To solve this problem store the previous position and the position after the write to calculate the number of bytes written.

References write().

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

• largeFileFunctions.h