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【操作系统】信号量的用法

星拱北辰发布时间：2021-01-30 22:43:27 ，浏览量：4

文章目录

信号量
整型信号量
记录型信号量
信号量解决同步问题
信号量解决互斥问题
信号量实现前驱关系
案例分析
补充说明

信号量

信号量，Semaphore，是一种较强的机制，是解决互斥和同步的问题的方法之一。

Semaphore只能被两种标准原语来访问：

P - wait(S)
V - signal(S)

整型信号量

整型信号量被定义为一个用于表示资源数目的整型量S，非负，wait(S)和signal(S)操作可描述为：

wait(S) {
   
    while(S


    
        
            
                
                
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