Copy-on-write
(sometimes referred to as "COW") is an optimization
strategy used in computer programming
.
The fundamental idea is that if multiple callers ask for resources
which are initially indistinguishable, they can all be given pointers to
the same resource. This function can be maintained until a caller tries
to modify its "copy" of the resource, at which point a true private
copy is created to prevent the changes becoming visible to everyone
else. All of this happens transparently
to the callers. The primary advantage is that if a caller never makes any modifications, no private copy need ever be created.
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NULL 博文链接:https://pingfang.iteye.com/blog/1485535
参考陈硕的多线程服务端编程>>,中的用shared_ptr实现copy-on-write技术,不过这里的线程采用的是c++11的线程库
下面小编就为大家带来一篇详谈Linux写时拷贝技术(copy-on-write)必看篇。小编觉得挺不错的,现在就分享给大家,也给大家做个参考。一起跟随小编过来看看吧
里,我想从C++类或是设计模式的角度为各位揭开Copy-On-Write技术在string中实现的面纱,以供各位在用C++进行类库设计时做一点参考
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