memory mapped files c tutorial

InterpretationMemory-mapped files (memeory-mapped file) is a mechanism of memory management of the operating system itself, and its idea is to keep a certain area of address space and submit the physical memory to this region. The physical

Original link: http://blogs.msdn.com/salvapatuel/archive/2009/06/08/working-with-memory-mapped-files-in-net-4.aspxPre-Knowledge: This article requires you to have a certain understanding of OS memory management.I want to explore some of the new features in the upcoming. NET 4, rather than the dynamic types, covariance,

In this lesson we'll talk about memory-mapped files and demonstrate how to use them. You will find that using memory-mapped files is very simple.Theory:If you have studied the example of the previous lesson carefully, you will fin

Absrtact: This paper gives a convenient and practical method to solve the processing of large file reading and storage, and introduces the specific implementation process with the relevant program code. Introduction File operations are one of the most basic functions of an application, WIN32 APIs and MFC provide functions and classes that support file handling, and are commonly used with Win32 API CreateFile (), WriteFile (), ReadFile (), and MFC-provided CFile classes. Generally speaking, the

#作用: Create a memory-mapped file instead of reading the content directlyText message content: as follows (name is Text.txt)Lorem ipsum dolor sit amet, consectetuer adipiscing elit. DonecEgestas, enim et consectetuer ullamcorper, lectus ligula rutrum Leo,A elementum elit tortor EU quam.Duis tincidunt nisi ut ante. NullaFacilisi.Sed tristique eros eu libero. Pellentesque velArcu. Vivamus purus Orci, iaculis a

Brief introduction:Memory-mapped files are somewhat similar to virtual memory, where a memory-mapped file preserves an area of an address space and submits the physical memory to this zone, except that the physical

, but supports R and RW access modes) 1.4) Only Randomaccessfile has a seek search method, and this method applies only to files. Bufferedinputstream has a mark () method that you can use to set the tag (save the result in an internal variable), and then call Reset () to return to that position, but it is too weak and not practical. (the function of seek in dry--randomaccessfile is equivalent to the combination of the Mark method and th

The memory-mapped file (mappedbytebuffer) of Java NIO makes me immediately associate the memory-mapped file of the Windows system. The memory-mapped file of a Windows system can be used to share data among multiple processes, that

dataoutputstream, plus some of its own methods, such as the getfilepointer of positioning (), The Seek () to be moved in the file, and the number of bytes to determine the length (), skipbytes () of the file size skipped. In addition, its constructor has a parameter that indicates whether to open the file as read-only ("R") or read-write ("RW") (fopen () of C). It does not support write-only files.Only Randomaccessfile has a seek search method, and this method applies only to

number of "readable" data in buffer, or the number of new data that can be "written", returning a limit-position;⑦, int position () returns the value of the current position;⑧, int capacity () returns the value of the capacity in buffer;Ii. file mapping for NiOLet's look at the new enhancements to the Java.nio package with respect to the old IO:NiO mainly supports four enhanced features:Encoding and decoding of ① and character sets;②, non-blocking IO (nonblocking I/O);③, memmory-

For some small files, with ordinary file stream can be a good solution, but for large files, such as 2G or more, the file stream is not, so to use the API's memory mapping method, even the memory map, can not map the size of all files at once, so you must take a block map, H

Want to do EXE, DLL communication, Online said more is Wm_copydata message, found that need to add a message map more trouble, and the Internet is almost MFC code, want to use the console code.I thought of the memory-mapped file. EXE sends data to the DLL.EXE's code:/**************************************************************************************** file name: test.cpp* Energy: EXE and DLL communicati

Want to do EXE, DLL communication, Online said more is Wm_copydata message, found that need to add a message map more trouble, and the Internet is almost MFC code, want to use the console code.I thought of the memory-mapped file. EXE sends data to the DLL.EXE's code:/**************************************************************************************** file Name: test.cpp* function: EXE and DLL communicat

1. MmapMmap can map a portion of a disk file directly to memory, so that the location of the file directly has a corresponding memory address, read and write to the file can be directly with the pointer without the need for the Read/write function.Shared memory Exchange data, not switch the power level, fast.Mmap Cons: 1) consumes

Original: http://blog.csdn.net/wangtiewei/article/details/51112668A memory-mapped file uses virtual memory to map a file to the address space of a process, after which the process operates the file as if it were an address in the process space, such as a function that uses memory operations such as C-memcpy. This metho

There are two models for node communication: Shared memory and Messages passing ). Memory ing files seem unfamiliar to developers hosting the world, but they are indeed Ancient technology and have a considerable position in the operating system. In fact, any communication model that wants to share data will use it behind the scenes. What is the

There are three ways in which memory management works:1. Virtual memory, functions such as VirtualAlloc2. Heap, heapxxx function, malloc,new, etc.3. Memory-mapped files, Mapped fileVery many people will be confused, but look at th