{"id":304,"date":"2025-09-08T20:45:06","date_gmt":"2025-09-08T12:45:06","guid":{"rendered":"http:\/\/www.tgwttt.xyz\/?p=304"},"modified":"2025-11-24T16:37:16","modified_gmt":"2025-11-24T08:37:16","slug":"posix%e4%bf%a1%e5%8f%b7%e9%87%8f","status":"publish","type":"post","link":"https:\/\/www.tgwttt.xyz\/?p=304","title":{"rendered":"POSIX\u4fe1\u53f7\u91cf"},"content":{"rendered":"\n

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#include\n#include\n#include\nnamespace SemModule{\n    class Sem{\n        public:\n            Sem(unsigned int value=1){\n                sem_init(&sem_,0,value);\n            }\n            ~Sem(){\n                sem_destroy(&sem_);\n            }\n            void P(){\n                sem_wait(&sem_);\/\/\u539f\u5b50\u64cd\u4f5c\n            }\n            void V(){\n                sem_post(&sem_);\n            }\n        private:\n            sem_t sem_;\n    };\n}<\/code><\/pre>\n\n\n\n
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#include <\/p>\n\n\n\n
int sem_init(sem_t *sem, int pshared, unsigned int value);<\/p>\n\n\n\n
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value\uff1a\u4fe1\u53f7\u91cf\u521d\u59cb\u503c<\/p>\n\n\n\n
\u9500\u6bc1\u4fe1\u53f7\u91cf \uff1a
int sem_destroy(sem_t *sem);
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int sem_wait(sem_t *sem); \/\/P()
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int sem_post(sem_t *sem);\/\/V()
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\"\"<\/figure>\n\n\n\n
#pragma once\n#include\n#include\"Sem.hpp\"\nstatic const int gcap=5;\nusing namespace SemModule;\ntemplate \nclass RingQueue {\n    private:\n       std::vector_rq;\n        int _cap;\n        Sem _blank_sem;\/\/\u8868\u793a\u7a7a\u7684\u8d44\u6e90\n        Sem _data_sem;\/\/\u8868\u793a\u6570\u636e\u7684\u8d44\u6e90\n        int _p_step;\/\/\u6d88\u8d39\u8005\u4f4d\u7f6e\n        int _c_step;\/\/\u751f\u4ea7\u8005\u4f4d\u7f6e\n    public:\n       RingQueue(int size = gcap)\n    : _rq(size),\n      _cap(size),\n      _blank_sem(size),   \/\/ \u7a7a\u4f4d\u4e00\u5f00\u59cb\u662f\u6ee1\u7684\n      _data_sem(0),       \/\/ \u6570\u636e\u4e00\u5f00\u59cb\u662f\u7a7a\u7684\n      _p_step(0),\n      _c_step(0) {}\n\nvoid Enqueue(const T& in) {\n    _blank_sem.P();          \/\/ \u7533\u8bf7\u7a7a\u4f4d\n    _rq[_p_step] = in;\n    _p_step = (_p_step + 1) % _cap;\n    _data_sem.V();           \/\/ \u91ca\u653e\u6570\u636e\n}\n\nvoid Pop(T& out) {\n    _data_sem.P();           \/\/ \u7533\u8bf7\u6570\u636e\n    out = _rq[_c_step];\n    _c_step = (_c_step + 1) % _cap;\n    _blank_sem.V();          \/\/ \u91ca\u653e\u7a7a\u4f4d\n}\n\n};\n<\/code><\/pre>\n\n\n\n
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