rpa::mmap_ctrl Class Reference

List of all members.

Public Member Functions
	mmap_ctrl (int aFilDes, const visitor &aVisit, size_t aPagSiz)
bool	not_empty (void) const
Private Attributes
bool	_notEmpty
	Tells whether data were copied or not.
Classes
class	segment

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Detailed Description

The role of this class is to map the beginning of a file for reading only, and to handle the unmapping of memory, especially if an exception is thrown. It is very specific and used here only.

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Constructor & Destructor Documentation

rpa::mmap_ctrl::mmap_ctrl	(	int	aFilDes,
		const visitor &	aVisit,
		size_t	aPagSiz
	)			[inline]

The size to be mapped in memory may be too big, so it is splitted in a loop, and the functor is called for each segment.

The length argument of mmap has no size or alignment constraints.

The offset argument is constrained to be aligned and sized according to the value returned by sysconf when passed _SC_PAGESIZE or _SC_PAGE_SIZE. Anyway, the data starts from the beginning.

If the segment size is too big, it would be wise to shrink it and retry. Conversely, it may be good to gradually increase it.

If an exception is thrown, the segment will be unmapped.

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Member Function Documentation

bool rpa::mmap_ctrl::not_empty

(

void

)

const [inline]

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Member Data Documentation

bool rpa::mmap_ctrl::_notEmpty [private]

Tells whether data were copied or not.

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

• futilities.cpp

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