linux c++ 多进程 匿名管道 命名管道 消息队列 信号量 共享内存 内存映射

#include <stdio.h>#include <stdlib.h>#include <string.h>#include <fcntl.h>#include <unistd.h>#include <stdbool.h>#include <thread>#include <errno.h>#include <sys/wait.h>#include <sys/stat.h>#include <sys/types.h>#include <sys/msg.h>#include <sys/sem.h>#include <sys/shm.h>#include <sys/mman.h>//多进程//匿名管道命名管道//消息队列//信号量//共享内存//内存映射struct mymsg{long int msgtype;char data[BUFSIZ];};union semun{int val;struct semid_ds *buf;unsigned short int *arry;struct seminfo *__buf;};struct shmst{char name[20];int age;char str[100];};typedef struct shmst mmapst;void onexit(){fprintf(stderr, "%s\n", "onexit");}void on_exit_cb(int status, void* arg){fprintf(stderr, "on_exit_cb status = %d arg = %d \n", status, reinterpret_cast<size_t>(arg));}const char* buf = "hello ";int main(int argc, char* argv[]){pid_t pid;int fd;//----------------------------perror(argv[0]);//----------------------------//----------------------------atexit(onexit);on_exit(on_exit_cb, (void*)1);//----------------------------//----------------------------fd = open("a.txt", O_RDWR | O_TRUNC | O_CREAT, S_IRUSR | S_IWUSR);//----------------------------//----------------------------//管道int _pipe[2] = { 0 };int ret = pipe(_pipe);if (ret == -1){printf("pipe error %d", errno, strerror(errno));exit(-1);}//----------------------------//----------------------------//消息队列std::thread t([] {int msgid = msgget(1234, IPC_CREAT | 0666);if(msgid == -1)perror("msgget");struct mymsg msg2 = { 0 };while (true){ssize_t ret = msgrcv(msgid, &msg2, sizeof(mymsg) - sizeof(long int), 0, 0/*IPC_NOWAIT*/);if (ret == -1){perror("msgrcv error");}else if(ret > 0){if (strcmp(msg2.data, "end") == 0){printf("msgrec msg:%s\n", msg2.data);break;}}}msgctl(msgid, IPC_RMID, 0);});std::this_thread::sleep_for(std::chrono::seconds(2));//----------------------------unlink("./testsem.ini");if (open("./testsem.ini", O_RDWR | O_CREAT | O_TRUNC, 0666) == -1){perror("open");}//----------------------------//信号量key_t sem_key = ftok("./testsem.ini", 1);perror("ftok");int sem_id = semget(sem_key, 1, 0666 | IPC_CREAT);if (sem_id == -1){perror("semget");}union semun sem_union;sem_union.val = 1;if (semctl(sem_id, 0, SETVAL, sem_union) == -1){perror("semctl");}//----------------------------//----------------------------//共享内存int shm_id = shmget(key_t(12345), sizeof(struct shmst), 0666 | IPC_CREAT);if (shm_id == -1)perror("shmget");void* pbuf = shmat(shm_id, 0, 0);if (pbuf == NULL)perror("shmat");else{struct shmst* pshmst = (struct shmst*)pbuf;strcpy(pshmst->name, "lls");strcpy(pshmst->str, "hello lls");pshmst->age = 27;if (shmdt(pbuf) == -1)perror("shmdt");}//----------------------------//----------------------------//内存映射int mmap_fd = open("./mmap.temp", O_CREAT | O_RDWR | O_TRUNC, 0666);if (mmap_fd == -1)perror("open");write(mmap_fd, " ", sizeof(mmapst));//不加这句会报bus errormmapst* pmmapbuf = (mmapst*)mmap(NULL, sizeof(mmapst), PROT_READ | PROT_WRITE, MAP_SHARED, mmap_fd, 0);if (pmmapbuf == NULL)perror("mmap");strcpy(pmmapbuf->name, "lls");strcpy(pmmapbuf->str, "hello lls");pmmapbuf->age = 27;if (msync(pmmapbuf, sizeof(mmapst), MS_SYNC) == -1)perror("msync");if (munmap(pmmapbuf, sizeof(mmapst)) == -1)perror("munmap");close(mmap_fd);//----------------------------pid = fork();if (pid == -1){printf("%s", "fork error\n");exit(EXIT_FAILURE);}else if (pid == 0){//----------------------------close(_pipe[0]);write(_pipe[1], "abcde", 5);//----------------------------//----------------------------write(fd, buf, strlen(buf));close(fd);//----------------------------if (-1 == execl("/home/lls/projects/testfile/bin/x64/Debug/testfile.out", "lls", "luls", NULL)){perror("execl error");printf("execl error: %d: %s\n", errno, strerror(errno));}//execlp("ls", "l", NULL);//execle("ls", "l", NULL, "/bin");//char* const argv[] = {"ls", NULL};//execv("/bin/ls", argv);//execvp("ls", argv);//char* const envp[] = { "/bin", NULL };//execve("ls", argv, envp);//printf("i'm child child_pid = %d ppid = % d!\n", getpid, getppid);//exit(110);}//----------------------------int s = access("./temp.txt", 0);if (s != 0){ret = mkfifo("./temp.txt", 0666 | __S_IFIFO);if (ret == -1){perror("mkfifo error");}}int fifofd = open("./temp.txt", O_RDONLY);char* szb[10] = { 0 };read(fifofd, szb, 5);close(fifofd);printf("------------------------\n");printf("fifo:\n");fprintf(stderr, "read fifo : %s\n", szb);printf("------------------------\n");//----------------------------struct sembuf sem_b;sem_b.sem_num = 0;sem_b.sem_op = -1;sem_b.sem_flg = SEM_UNDO;if (semop(sem_id, &sem_b, 1) == -1){perror("semop");}//----------------------------close(_pipe[1]);char szbuf[10] = { 0 };read(_pipe[0], szbuf, 5);printf("------------------------\n");printf("pipe:\n");fprintf(stderr, "read pipe : %s\n", szbuf);printf("------------------------\n");//----------------------------printf("i'm parent pid = %d!\n", getpid());//----------------------------int status = 0;waitpid(pid, &status, 0);//----------------------------//----------------------------lseek(fd, 0, SEEK_SET);char buf2[100] = { 0 };ssize_t res = read(fd, (void*)buf2, 100);(void)res;close(fd);printf("%s\n", buf2);//----------------------------//----------------------------t.join();//----------------------------//----------------------------//struct sembuf sem_b;sem_b.sem_num = 0;sem_b.sem_op = 1;sem_b.sem_flg = SEM_UNDO;if (semop(sem_id, &sem_b, 1) == -1){perror("semop");}if (semctl(sem_id, 0, IPC_RMID, 0) == -1)perror("semctl");//----------------------------//----------------------------if (shmctl(shm_id, IPC_RMID, 0) == -1){perror("shmctl");}//----------------------------    return 0;}

#include <stdio.h>#include <string.h>#include <sys/stat.h>#include <fcntl.h>#include <unistd.h>#include <sys/msg.h>#include <sys/sem.h>#include <sys/shm.h>#include <sys/mman.h>struct mymsg{long int msgtype;char data[BUFSIZ];};union semun{int val;struct semid_ds* buf;unsigned short int* array;struct seminfo *__buf;};typedef struct shmst{char name[20];int age;char str[100];}mmapst;int main(int argc, char* argv[]){key_t sem_key = ftok("./testsem.ini", 1);int sem_id = semget(sem_key, 1, 0666 | IPC_CREAT);if (sem_id == -1){perror("semget");}/*union semun sem_union;sem_union.val = 1;if (semctl(sem_id, 0, SETVAL, sem_union) == -1){perror("semctl");}*/struct sembuf sem_bf;sem_bf.sem_num = 0;sem_bf.sem_op = -1;sem_bf.sem_flg = SEM_UNDO;if (semop(sem_id, &sem_bf, 1) == -1){perror("semop");}printf("------------------------\n");//----------------------------//共享内存int shm_id = shmget(key_t(12345), sizeof(struct shmst), 0666 | IPC_CREAT);if (shm_id == -1)perror("shmget");void* pbuf = shmat(shm_id, 0, 0);if (pbuf == NULL)perror("shmat");else{struct shmst* pshmst = (struct shmst*)pbuf;printf("------------------------\n");printf("shm:\n");printf("name:%s\n", pshmst->name);printf("str:%s\n", pshmst->str);printf("age:%d\n", pshmst->age);printf("------------------------\n");if (shmdt(pbuf) == -1)perror("shmdt");}//----------------------------//----------------------------//内存映射int mmap_fd = open("./mmap.temp", O_RDONLY);if (mmap_fd == -1)perror("open");mmapst* pmmapbuf = (mmapst*)mmap(NULL, sizeof(mmapst), PROT_READ, MAP_SHARED, mmap_fd, 0);if (pmmapbuf == NULL)perror("mmap");printf("------------------------\n");printf("mmap:\n");printf("name:%s\n", pmmapbuf->name);printf("str:%s\n", pmmapbuf->str);printf("age:%d\n", pmmapbuf->age);printf("------------------------\n");if (munmap(pmmapbuf, sizeof(mmapst)) == -1)perror("munmap");close(mmap_fd);//----------------------------key_t key = 1234;int msgid = msgget(key, 0666 | IPC_CREAT);printf("msgget msgid = %d\n", msgid);struct mymsg msg = { 0 };msg.msgtype = 1;strcpy(msg.data, "end");if (-1 == msgsnd(msgid, &msg, sizeof(mymsg) - sizeof(long int), 0)){perror("msgsend error");}printf(argv[0]);printf("\n");printf(argv[1]);printf("\n");    printf("hello from testfile!\n");char path[1024] = { 0 };getcwd(path, 1024);printf(path);printf("\n");int s = access("/home/lls/projects/testprocess/bin/x64/Debug/temp.txt", 0);if (s == 0){//unlink("/home/lls/projects/testprocess/bin/x64/Debug/temp.txt");}else{int ret = mkfifo("/home/lls/projects/testprocess/bin/x64/Debug/temp.txt", 0666 | __S_IFIFO);if (ret == -1){perror("mkfifo error");}}int fifofd = open("./temp.txt", O_WRONLY);write(fifofd, "edcba", 5);close(fifofd);printf("------------------------\n");sem_bf.sem_num = 0;sem_bf.sem_op = 1;sem_bf.sem_flg = SEM_UNDO;if (semop(sem_id, &sem_bf, 1) == -1){perror("semop");}    return 0;}