1 //processA.c文件 2 #include <stdlib.h> 3 #include <stdio.h> 4 #include <sys/shm.h> 5 #include <unistd.h> 6 #include <string.h> 7 #include <sys/types.h> 8 #include <sys/ipc.h> 9 #include <errno.h> 10 #include <pthread.h> 11 12 #define BUF_SIZE 4096 13 14 int main() 15 { 16 void *shm_addr = NULL; 17 char buffer[BUF_SIZE]; 18 pthread_mutex_t * sharedLock; 19 pthread_mutexattr_t ma; 20 21 int shmid; 22 // 使用约定的键值创建共享内存 23 shmid = shmget((key_t) 1234, BUF_SIZE, 0666 | IPC_CREAT); 24 printf("shmid : %u\n", shmid); 25 if (shmid < 0) 26 { 27 perror("shmget error!"); 28 exit(1); 29 } 30 31 // 将共享内存附加到本进程 32 shm_addr = shmat(shmid, NULL, 0); 33 if (shm_addr == (void *) -1) 34 { 35 perror("shmat error!"); 36 exit(1); 37 } 38 39 sharedLock = (pthread_mutex_t *)shm_addr; 40 41 pthread_mutexattr_init(&ma); 42 pthread_mutexattr_setpshared(&ma, PTHREAD_PROCESS_SHARED); 43 pthread_mutexattr_setrobust(&ma, PTHREAD_MUTEX_ROBUST); 44 pthread_mutex_init(sharedLock,&ma); 45 46 // 写入数据 47 while(1){ 48 pthread_mutex_lock(sharedLock); 49 bzero(buffer, BUF_SIZE); 50 sprintf(buffer, "Hello, My PID is %u\n", (unsigned int) getpid()); 51 printf("send data: %s\n", buffer); 52 memcpy(((pthread_mutex_t *)shm_addr)+1, buffer, strlen(buffer)); 53 pthread_mutex_unlock(sharedLock); 54 } 55 56 sleep(5); 57 58 // 分离 59 if (shmdt(shm_addr) == -1) 60 { 61 printf("shmdt error!\n"); 62 exit(1); 63 } 64 }View Code 进程B:
1 //processB.c文件 2 #include <stdio.h> 3 #include <stdlib.h> 4 #include <sys/shm.h> 5 #include <sys/ipc.h> 6 #include <sys/types.h> 7 #include <unistd.h> 8 #include <string.h> 9 #include <errno.h> 10 #include <pthread.h> 11 12 #define BUF_SIZE 4096 13 14 int main() 15 { 16 void *shm_addr = NULL; 17 pthread_mutex_t * sharedLock; 18 char tmp[BUF_SIZE]; 19 20 int shmid; 21 // 使用约定的键值打开共享内存 22 shmid = shmget((key_t) 1234, BUF_SIZE, IPC_CREAT); 23 printf("shmid : %u\n", shmid); 24 if (shmid == -1) 25 { 26 perror("shmget error!"); 27 exit(1); 28 } 29 30 // 将共享内存附加到本进程 31 shm_addr = shmat(shmid, NULL, 0); 32 if (shm_addr == (void *) -1) 33 { 34 perror("shmat error!"); 35 exit(1); 36 } 37 38 sharedLock = (pthread_mutex_t *)shm_addr; 39 40 // 读取数据 41 while(1){ 42 pthread_mutex_lock(sharedLock); 43 bzero(tmp, BUF_SIZE); 44 memcpy(tmp, ((pthread_mutex_t *)shm_addr)+1, 50); 45 printf("read from shared memory: %s\n", tmp); 46 pthread_mutex_unlock(sharedLock); 47 } 48 49 sleep(5); 50 51 // 分离 52 if (shmdt(shm_addr) == -1) 53 { 54 printf("shmdt error!\n"); 55 exit(1); 56 } 57 58 // 删除共享内存 59 if (shmctl(shmid, IPC_RMID, 0) == -1) 60 { 61 printf("shmctl error!\n"); 62 exit(1); 63 } 64 }View Code