mmap file format

vma type must perform these operations in the vector table. the following operations are included: open, close, unmap, protect, sync, nopage, wppage, and swapout. Struct vm_area_struct { /* Public, irrelevant to vma type */ Struct mm_struct * vm_mm; Unsigned long vm_start; Unsigned long vm_end; Struct vm_area_struct * vm_next; Pgprot_t vm_page_prot; Unsigned long vm_flags; Short vm_avl_height; Struct vm_area_struct * vm_avl_left; Struct vm_area_struct * vm_avl_right; Struct vm_area_struct * vm_

Original: http://weibo.com/p/1001603830912709174661Write mmap memory and file generates hundreds of MS latency reasonApril 12, 2015 21:10 reading 4274 Recently saw a bug introduction, the author spent 4 months tracking location, found that the JVM statistics will cause the garbage collection process to pause good hundreds of Ms. The JVM statistics are written to a memory area that

/ * Use Mmap to operate the file * /#include #include #include #include #include #include #define FILELENGTHintMainvoid){intFD =-1;/ * The string that will be written to the file * / Charbuf[]="Quick brown fox jumps over the lazy dog";Char*ptr = NULL;/* Open the file mmap.txt and reduce the

void *mmap (void *addr, size_t length, int prot, int flags, int fd, off_t offset);function function: Map the contents of the file to a piece of memory (virtual memory), through the memory read and modify, to achieve the file read and modify.Parameter descriptionAddr: Specifies the starting address of the map, usually set to null (indicated by the system).Length:

Disk-to-memory mapping is a file mapping, before we say the swap, because This problem makes me very easy to think of Swap,linux swap is the meaning of the swap partition, in the case of memory not enough, the operating system first put the memory and the swap area of the disk to "map", and then the these memory freed up into memory, For the subsequent process of freeing up a piece of memory space, wait until the own process is awakened again, then

This article describes the POSIX environment uses file mapping IO method of operation, file mapping IO also known as storage mapping IO , for ordinary files, many times it is efficient, it actually reduces the duplication of data, and it can also be used in special places for communication between processes, a way of sharing memory. We can think of a file as a co

MMAP can map a part of the disk file directly to the memory, so that the location in the file has a corresponding memory address, you can directly use pointers to read and write files without the need for the read/write function. Prototype: # include Void * MMAP (void * ADDR, size_t Len, int Prot, int flag, int fi

Best references: 1. Master from the Internet. 2. UNP V2 posix ipc chapter 12. 3. Linux man command. Article 1: MMAP function Purpose 1. Map common files to the process memory space for memory ing Io. 2. Map special files to the process memory space for anonymous memory ing Io. 3. Map shm_open to open the POSIX shared memory zone to the memory space of the process, which can provide data sharing and IO among unrelated processes. # Include V

Copy the Code code as follows: /********************* @file-path to File*/function Force_download ($file){if ((Isset ($file)) (File_exists ($file))) {Header ("Content-length:". FileSize ($file));Header (' Content-type:applicati

Every time a new file is opened in ultraedit, the following message is displayed: "The file may not be in the DOC format. Do you want to convert the file to the doc format ?" Every time, I feel very troublesome. It is also annoying. The following prompt can be removed from t

Tags: designing mysql with file data management database SQLFrm,myd,myi is a file that belongs to MySQL storage data, phpMyAdmin cannot be imported.phpMyAdmin supports file formats for SQL files.It's actually very simple:1. Find your MySQL installation directory in the Data folder, create a new folder, the name of the folder is the name of the library you want to

This series of articles are all copied from msdn. Remember them first, and they will be translated step by step later. Due to my limited level of English, the translation may not be completely correct. Please note that. Avi riff file reference This is preliminary documentation and subject to change. (The Microsoft AVI file format is a riff

algorithm is as follows:Int FSize;FSize = Size [0] x 0x100000000+ Size [1] x 0x10000+ Size [2] x 0x100+ Size [3]; (3). Flag Only 6 bits are defined, and the other 10 bits are 0, but in most cases, 16 bits are all 0. The format is as follows:Abc00000 ijk00000A -- tag protection flag, which is regarded as void when setB -- indicates the file protection flag. This frame is considered invalid when it is set.C

Recently in making a voice changer app, which used the PCM format to wave format, the following posted source code, hope that with the needs of children's shoes help!!! This is written in the C + + language, or it can be implemented in Java. Of course, Java calls the native function to use the JNI technique. Specific JNI technology to find information on the Internet itself.CPP

Use this VBS code to create Excel:Set oexcel=createobject ("Excel.Application") oexcel. Workbooks.Add () oexcel. ActiveWorkbook.SaveAs ("D:\xx.xls") ' oexcel. Quitset oexcel=nothingHowever, when you create an Excel that opens, you are prompted with "the format of the file you are trying to open is inconsistent with the format specified by the

Detailed description of zip file format (1) -- file data format ---------------------------------------------------------------------------------- Document Description Zip compression is one of our common compression formats. He has many users around the world with its versatility and high compression ratio. This arti

The picture below is. X file opened by DirectX Mesh View. today, we look at the X file's detail information. I stronugly recommand readers search "X File Format Reference" topic in DirectX SDK documentation. The variable-length header is compulsory and must be at the beginning of the data stream. The header contains the following data. Type Required Size

ELF File Format learning in C language, elf File Format Recently, ELF files are related to the lab, so this is almost the case. Learn about ELF. ELF is a file format. For the time being, only the ELF

For more information about 'file storage format' and 'file content format ', Something about 'file storage format' and 'file content format'

For detailed format descriptions, see: 1. Intel Hexadecimal Object File Format Specification 1988 (PDF), Revision A, January 6, 1988 2. http://en.wikipedia.org/wiki/Intel_hex ______________________________________________________________________________________________ What is Intel HEX format? An Intel HEX