linux无亲缘关系间进程同步通信实现（互斥锁+条件变量+共享内存模式）

/* * Copyright (C) 2013 yangguo <yangguo@yangguo-ubuntu 12.4LTS> * project name:commonModel * created time:2013-07-07-09.45 * company:www.dbc.com * support email:guoyang2011@gmail.com * version:0.1 * main function:None * modify information:None */ #include <sys/mman.h> #include <string.h> #include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <sys/stat.h> #include <sys/wait.h> #include <pthread.h> struct sharedmemory { pthread_mutex_t mutex; pthread_cond_t isReadCond; pthread_cond_t isWriteCond; int condition; char data[80]; }; #define SHAREDMEMORYFILE "data.d" int main() { int fd; int i=0; int memorySize; pthread_mutexattr_t mutexAttr; pthread_condattr_t condAttr; struct sharedmemory *ptr; memorySize=sizeof(struct sharedmemory); fd=shm_open(SHAREDMEMORYFILE,O_CREAT|O_TRUNC|O_RDWR,0777); if(-1==fd) { printf("Shared shm_open\n"); exit(0); } if(ftruncate(fd,memorySize)) { printf("Shared ftruncate\n"); exit(0); } ptr=mmap(NULL,memorySize,PROT_READ|PROT_WRITE,MAP_SHARED,fd,0); if(ptr==MAP_FAILED) { printf("Shared MAP_FAILED\n"); exit(0); } close(fd); pthread_mutexattr_init(&mutexAttr); pthread_mutexattr_setpshared(&mutexAttr,PTHREAD_PROCESS_SHARED); pthread_condattr_init(&condAttr); pthread_condattr_setpshared(&condAttr,PTHREAD_PROCESS_SHARED); pthread_mutex_init(&ptr->mutex,&mutexAttr); pthread_cond_init(&ptr->isReadCond,&condAttr); pthread_cond_init(&ptr->isWriteCond,&condAttr); ptr->condition=0; strcpy(ptr->data,""); while(1) { pthread_mutex_lock(&ptr->mutex); while(ptr->condition!=0) { printf("++++++++++parent waiting for condition become true!\n"); pthread_cond_wait(&ptr->isWriteCond,&ptr->mutex); } gets(ptr->data); printf("++++++++++parent change Condition value:%d\n",++ptr->condition); pthread_mutex_unlock(&ptr->mutex); if(ptr->condition) { printf("++++++++++parent send signal for parent read data!\n"); pthread_cond_signal(&ptr->isReadCond); } printf("+++++++++++parent Current %d loop is over!\n\n\n",i); if(strcmp(ptr->data,"exit")==0) { break; } i++; } shm_unlink(SHAREDMEMORYFILE); exit(0); return 0; }