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This article will explain in detail the example analysis of memory management in C++. The editor thinks it is very practical, so I share it for you as a reference. I hope you can get something after reading this article.

Overview

The principle of memory management is huge and complex, but these are encapsulated by the operating system and reserved for API. These api are called by C++, and also encapsulated by C++ again, and then reserved for programmers. As programmers using C++, we only need to master the memory management features reserved by C++. Just like when we drive, we don't need to control the variable box, how the engine changes speed, how to ignite, we just need to know the interface that the car has reserved for us, and how to use the steering wheel, brakes and throttle.

C++ programs are easy to produce bug, mainly because of the complexity of memory management, java, python and other languages provide more encapsulation, so reduce the difficulty of operation and the possibility of errors for programmers. Just like an automatic car, without the clutch, the gearbox will not be damaged by operational error.

C++ free memory available memory for language c

In C language, our available memory is mainly divided into the following areas:

Stack, used to store local variables.

Global data area / static data area, used to store global variables and static local variables.

Const data area, which is actually not partitioned in memory, exists in the global data area or stack. Const cannot be modified by the compiler. There is no read-only memory in physical memory at all. So sometimes when we talk about zoning, we don't mention const because it doesn't exist independently at all.

Code snippet, of course, is used to store code. Under linux, our executable code is read from rom to memory for execution. Although memory is readable and writable, this memory is also a read-only but not write-only area under the monitoring of the operating system.

Heap, the heap in c is requested by malloc, freed by free, and the bottom layer is also a piece of memory provided to our program by the operating system.

New memory area for C++

All the memory partitions in c exist in C++, while C++ adds a free storage area, which is applied for by new and freed by delet. There is a memory zone between actual and malloc applications. Examples of memory used by new are as follows:

Int * p = new int;*p=6;cout java virtual machine-> Java bytecode-> java source code

From the above architecture, we can see that java is three layers more than cjava +. The source code of java is compiled and output is not cpu executable machine code, but is compiled into java bytecode. This thing is completely defined by java and can only run on JVM (java virtual machine). JVM runs based on some frameworks provided by the kernel, so java is an interpretive language, which is interpreted entirely by JVM. The source code is directly compiled into cpu executable machine code. Because of JVM, java can run across platforms, and java can be run wherever there is JVM, as long as the JVM of different platforms are compatible, and the running stability of java depends on JVM.

Garbage collection mechanism of java

Java has a daemon for garbage collection, the GC thread, which internally uses GC mechanisms and algorithms to get variable objects at the end of the life cycle and collect them as garbage.

In fact, garbage collection is not a patent of java, other languages, such as c # also have similar design concepts, typical is that they do not have pointers, its garbage collection mechanism allows programmers to avoid considering the life cycle of objects and the application and release of resources, making this language very easy to learn, in fact, garbage collection mechanisms are all at the cost of efficiency and memory resources, in exchange for easy to make mistakes, simple and easy to use.

This is the end of the article on "example Analysis of memory Management in C++". I hope the above content can be helpful to you, so that you can learn more knowledge. if you think the article is good, please share it for more people to see.

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