mmap mindmap

Recently I want to organize some things, so I need to use a brain chart. But do not want to install mindmanage or freemain. I like the former but it is too big. If you often use mindmap, we recommend that you install it. Freemind is very powerful and free, but you need to install the Java virtual machine, so I don't want to install it. Google, I found that there are still a lot of online brain images, so I don't need to carry the device. And you can u

about Dockwindow. Cpp:1#include"mainwindow.h"2#include 3#include 4 5Mainwindow::mainwindow (Qwidget *parent):6 7 Qmainwindow (parent)8 {9Setwindowtitle ("Mindmap");//Set Window captionTenQtextedit *te=NewQtextedit ( This);//this is replaced by the parent to run the same result, because C + + and QT are both fast so this problem is put here first =-= OneTe->setalignment (Qt::aligncenter);//setting alignment is the property->aligncenter the edit box oc

-domain error causes the local file Gtor.json to be inaccessible:This example must be deployed to the server to run.For the sake of simplicity, I made a simple package. If you want to run an example to see the effect, just download my project to Local: https://github.com/i042416/jerrylistStart the server directly locally with the Nodejs command line: Node Local.js Then Localhost:3000/mindmap can see the effect of mind mapTo get more orig

Linux(Flowchart,UML, Mindmap)Tools From http://my.opera.com/88djy/blog/show.dml/741663? Show = Login There is no easy-to-use drawing at hand for new projects.ToolsI prefer mindmap.ToolsButLinuxFreemind has never been used to, but its functions are not perfect. I prefer mindjet mindmanager, but unfortunately I don'tLinuxVersion, and flowchart, etc. FamiliarLinuxFriends may say that the graph made with Dia and Dia is too simple, so after a good Google,

Turn from: http://www.perfgeeks.com/?p=723 Mmap () and MMAP2 () are often visible through strace statistical system calls. System call MMAP () can map a file to memory (process space). This allows the operation of the file to be converted to memory operations to avoid more lseek () and read (), write () operations, which is especially beneficial for large files or frequently accessed files. But one thing

Linux system programming: inter-process communication-mmap, linux-mmap Inter-process communication-mmap #include In essence, mmap synchronizes the memory with files on the hard disk. The content in a memory is synchronized to the hard disk file, that is, the file is mapped to the memory. Therefore, communication be

shared memory area is again established. Instead, keep the shared area until the communication is complete so that the data content is kept in shared memory and not written back to the file. Content in shared memory is often written back to the file when the mapping is released. Therefore, the use of shared memory communication mode is very high efficiency. The Linux 2.2.x kernel supports a variety of shared memory modes, such as mmap () system calls

Shared Memory-memory ing MMAP Shared memory is the most useful method for inter-process communication and the fastest IPC format. The shared memory of two different processes A and B means that the same physical memory is mapped to the process address spaces of process a and process B. Process A can immediately see the updates to data in the shared memory of process B, and vice versa. Because multiple processes share the same memory area, a synchron

The previous article learned about shared memory: http://www.cnblogs.com/charlesblc/p/6142139.htmlAccording to this http://blog.chinaunix.net/uid-26335251-id-3493125.htmlOne more article:1. Shared memory allows two or more processes to share a given store, because the data does not need to replicate back and forth, so it is the fastest inter-process communication mechanism. Shared memory can be implemented through the mmap () mapping of ordinary files

Note: The android underlying malloc is swapped for mmap to get memory, the acquired memory can be added to the tag, so that the meminfo for analysis, you can view the memory of the tag separately for analysis.One. Mmap system call1. Mmap system callMmap maps a file or other object into memory. Files are mapped to multiple pages, and if the size of the file is not

Reprinted from Http://blog.chinaunix.net/uid-26669729-id-3077015.htmlOne. Mmap system call1. Mmap system callMmap maps a file or other object into memory. Files are mapped to multiple pages, and if the size of the file is not the sum of the size of all pages, the space that is not used by the last page will be zeroed out. Munmap performs the opposite operation by deleting the object mappings for a specific

Memory Allocation in linux: mmap, munmp, brk, mmapbrk Linux virtual memory management has several key concepts: 1. Each process has an independent virtual address space. The virtual address accessed by the process is not a real physical address; 2. The virtual address can be mapped to the physical address through the page table on each process (in the kernel virtual address space of each process) to obtain the real physical address; 3. If the physica

In Linux, MMAP and mmap2 are called to create a process address space ing. MMAP and mmap2 are commonly used in the following scenarios: 1. file ing common file I/O operations, read and write the memory after MMAP ing, you can complete file read and write operations, kernel and userspace operations are the same physical memory; while regular file read and write op

Http://blog.csdn.net/edwardlulinux/article/details/8604400 Many articles have analyzed the implementation principle of MMAP. From the logic of the code, I always feel that the read/write ing area after MMAP is not associated with the common read/write areas. Have to have questions: 1. What is the difference between reading and writing in the ing areas after the common read/write and

1. Introduction to shared memory The shared memory zone is the fastest form of IPC. data transmission between these processes no longer involves the kernel. In other words, processes no longer transmit data by executing system calls that enter the kernel. That is, each process address space has a shared storage ing area. When this area is mapped to the same real physical address space, data exchange can be performed through this area, for example, the shared library is implemented in this way.

Recently, the instructor said this: MMAP () memory ing can be used to copy files, and the speed is significantly faster than normal file copying.I tried to copy two files at a time.First, check the Code: # Include # Include# Include # Include# Include # Include# Include # Include # Include# Include # DefineBuffer_size 1 Void my_copy1 (){Int fin, fout;Void * start;Void * end;Struct stat Sb;If (fin =Open ("file. In", o_rdonly) Perror ("Open error ");Ex

You can't simply say which method is highly efficient. Either method is nothing more than the OS that helps you cache your memory, and then the fl at some point in time. To the memory. MMAP can easily simplify file operations and is more efficient than Directly Reading and Writing files. Introduced a few paragraphs: "This problem is complicated and it cannot be simply said that MMAP is faster tha

Memory mapping is one of the most interesting features of modern Unix systems. As for drivers, memory mappings can be implemented to provide direct access to device memory by user programs. A clear example of a mmap usage can be seen from a subset of the virtual memory areas that are viewed to the X Windows system server: Cat/proc/731/maps 000a0000-000c0000 rwxs 000a0000 03:01 282652/dev/mem 000f0000-00100000 r-xs 000f0000 03:01 282652/dev/mem 004000

From: http://blog.csdn.net/scorpio16/article/details/2059623 The second volume of UNIX Network Programming inter-process communication describes MMAP functions. This function has three main purposes:1. Map a common file to the memory, which is usually used when files need to be read and written frequently. In this way, I/O reading and writing is replaced with memory reading and writing to achieve high performance;2. Anonymous memory ing of special fil

1. Introduction The following functions call MMAP in user State: void* mmap( void* addr, size_t size, int prot, int flags, int fd, long offset ) Then go to system call. 2. kernel MMAP implementation 1) then go to the system call. The system call number is: Kernel/ARCH/ARM/include/ASM/unistd. h # DEFINE _ nr_mmap2 (_ nr_syscall_base + 192) 2) Soft Interr