linux ipc/its
linux线程间消息队列
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <unistd.h>
#include <sys/ipc.h>
#include <sys/msg.h>
typedef struct {
long type;
char buf[100];
}msg_t;
void *write_routine(void *arg)
{
int msgid = *(int *)arg;
msg_t msg;
while(1)
{
msg_t msg={1,"login"};
int res = msgsnd(msgid,&msg,sizeof(msg.buf),IPC_NOWAIT);
sleep(1);
}
}
void *read_routine(void *arg)
{
int msgid = *(int *)arg;
msg_t msg;
//while(1)
//{
int res = msgrcv(msgid,&msg,sizeof(msg_t),1,0);
if(res==-1){
//perror("msgrcv");
}
switch (msg.type) {
case 1: {
printf("++++%s\n",msg.buf);
break;
}
case 2: {
printf("++++++++++++%s\n",msg.buf);
break;
}
}
// sleep(1);
//}
}
int main()
{
pthread_t wid;
pthread_t rid;
int msgid = msgget(1234,IPC_CREAT|0666);
if(msgid==-1)
{
perror("msgget");
}
int res = pthread_create(&wid,0,write_routine,&msgid);
if(res){
printf("%s\n",strerror(res));
}
int res2 = pthread_create(&rid,0,read_routine,&msgid);
if(res2){
printf("%s\n",strerror(res2));
}
pthread_join(wid,0);
pthread_join(rid,0);
return 0;
}
gcc -o msg msg.c -pthread
linux进程间双向消息队列
server.c
#include <stdio.h> #include <stdlib.h> #include <string.h> #include <pthread.h> #include <unistd.h> #include <sys/ipc.h> #include <sys/msg.h> typedef struct { long type; int id; char buf[100]; }msg_t; void *write_routine(void *arg) { key_t key = ftok("/",'a'); if(key==-1) { perror("ftok"); } int msqid = msgget(key,IPC_CREAT|0666); if(msqid==-1) { perror("msgget"); } msg_t msg; while(1) { msg.type = 2; msg.id = 2; fgets(msg.buf,100,stdin); //msg_t msg={1,"login"}; int res = msgsnd(msqid,&msg,sizeof(msg.buf),IPC_NOWAIT); } } void *read_routine(void *arg) { key_t key = ftok("/",'b'); if(key==-1) { perror("ftok"); } int msqid = msgget(key,IPC_CREAT|0666); if(msqid==-1) { perror("msgget"); } msg_t msg; while(1) { int res = msgrcv(msqid,&msg,sizeof(msg_t),1,IPC_NOWAIT); if(res==-1){ //perror("msgrcv"); } switch (msg.id) { case 1: { printf("%s\n",msg.buf); break; } case 2: { printf("%s\n",msg.buf); break; } } msg.id = 0; } } int main() { pthread_t wid; pthread_t rid; int res = pthread_create(&wid,0,write_routine,0); if(res){ printf("%s\n",strerror(res)); } int res2 = pthread_create(&rid,0,read_routine,0); if(res2){ printf("%s\n",strerror(res2)); } pthread_join(wid,0); pthread_join(rid,0); return 0; }
client.c
#include <stdio.h> #include <stdlib.h> #include <string.h> #include <pthread.h> #include <unistd.h> #include <sys/ipc.h> #include <sys/msg.h> typedef struct { long type; int id; char buf[100]; }msg_t; void *read_routine(void *arg) { key_t key = ftok("/",'a'); if(key==-1) { perror("ftok"); } int msqid = msgget(key,IPC_CREAT|0666); if(msqid==-1) { perror("msgget"); } msg_t msg; while(1) { int res = msgrcv(msqid,&msg,sizeof(msg_t),2,IPC_NOWAIT); if(res==-1){ //perror("msgrcv"); } switch (msg.id) { case 1: { printf("%s\n",msg.buf); break; } case 2: { printf("%s\n",msg.buf); break; } } msg.id = 0; } } void *write_routine(void *arg) { key_t key = ftok("/",'b'); if(key==-1) { perror("ftok"); } int msqid = msgget(key,IPC_CREAT|0666); if(msqid==-1) { perror("msgget"); } msg_t msg; msg.type = 1; msg.id = 1; //msg_t msg={1,"login"}; while(1) { fgets(msg.buf,100,stdin); int res = msgsnd(msqid,&msg,sizeof(msg_t),IPC_NOWAIT); } } int main() { pthread_t wid; pthread_t rid; int res = pthread_create(&wid,0,write_routine,0); if(res){ printf("%s\n",strerror(res)); } int res2 = pthread_create(&rid,0,read_routine,0); if(res2){ printf("%s\n",strerror(res2)); } pthread_join(wid,0); pthread_join(rid,0); return 0; }
Makefile
.PHONY:all all:server client server:server.c gcc -o server server.c -pthread client:client.c gcc -o client client.c -pthread .PHONY:clean clean: rm -f server client
https://blog.csdn.net/weixin_41215479/article/details/81511188
线程间消息
https://blog.csdn.net/qq_26391203/article/details/75220449
将共享内存改造成一个共享fifo，酷 ！
https://github.com/zhoudd1/linux_ipc/tree/master/shm_fifo
message queue
https://github.com/mdminhazulhaque/mqueue
1、nanomsg
nanomsg(ZeroMQ with C)
https://www.cnblogs.com/dong1/p/9213214.html
2、libmsgque
linux进程通信消息队列
https://gitee.com/fulinux/libmsgque
3、dbus
https://blog.csdn.net/quinta2008/article/details/78472170
linux ipc
1)signal
recv.c
#include <stdio.h> #include <signal.h> #include <sys/types.h> #include <unistd.h> void new_op(int,siginfo_t*,void*); int main(int argc,char**argv) { struct sigaction act; int sig; pid_t pid; pid=getpid(); sig=atoi(argv[1]); sigemptyset(&act.sa_mask); act.sa_sigaction=new_op; act.sa_flags=SA_SIGINFO; if(sigaction(sig,&act,NULL)<0) { printf("install sigal error\n"); } while(1) { sleep(2); printf("pid %d wait for the signal\n",pid); } } void new_op(int signum,siginfo_t *info,void *myact) { printf("the int value is %d \n",info->si_int); }
send.c
#include <stdio.h> #include <signal.h> #include <sys/time.h> #include <unistd.h> #include <sys/types.h> main(int argc,char**argv) { pid_t pid; int signum; union sigval mysigval; signum=atoi(argv[1]); pid=(pid_t)atoi(argv[2]); mysigval.sival_int=8; if(sigqueue(pid,signum,mysigval)==-1) printf("send error\n"); sleep(2); }
gcc -o recv recv.c
gcc -o send send.c
./recv 1
./send 1 39823
参考 https://www.ibm.com/developerworks/cn/linux/l-ipc/part2/index2.html
2）message queue
recv.c
#include <stdio.h> #include <string.h> #include <stdlib.h> #include <stdbool.h> #include <sys/ipc.h> #include <sys/msg.h> #include <errno.h> #define MSG_LEN 100 #define MSG_KEY 1234 //msg_queue typedef struct { long int type; char data[MSG_LEN]; }msg_t; static int msgid; //msg queue init int msg_queue_creat(key_t key) { msgid=msgget(key,0666 | IPC_CREAT); if(msgid==-1) { fprintf(stderr,"msgget failed with error: %d\n",errno); } return 0; } int main() { msg_queue_creat(MSG_KEY); while(1){ msg_t msg; if(msgrcv(msgid, &msg, sizeof(msg_t), 0, IPC_NOWAIT) == -1) { //fprintf(stderr,"msgrcv failed with error: %d\n",errno); } else printf("recv a message: %ld,%s\n",msg.type,msg.data); sleep(1); } }
send.c
#include <stdio.h> #include <string.h> #include <stdlib.h> #include <stdbool.h> #include <sys/ipc.h> #include <sys/msg.h> #include <errno.h> #define MSG_LEN 100 #define MSG_KEY 1234 //msg_queue typedef struct { long int type; char data[MSG_LEN]; }msg_t; static int msgid; //msg queue init int msg_queue_creat(key_t key) { msgid=msgget(key,0666 | IPC_CREAT); if(msgid==-1) { fprintf(stderr,"msgget failed with error: %d\n",errno); } return 0; } int main() { msg_queue_creat(MSG_KEY); while(1) { msg_t msg={1,"hello,world"}; if(msgsnd(msgid, &msg, sizeof(msg_t), IPC_NOWAIT) == -1) { //fprintf(stderr,"msgsnd failed with error: %d\n",errno); } else printf("send a message\n"); sleep(2); } }
参考 https://www.ibm.com/developerworks/cn/aix/library/au-ipc/
3） semaphore （命名信号量）
有名信号量实现进程间同步功能（print2 先打印，再到 print1 打印）
print1.c
#include <fcntl.h> /* For O_* constants */ #include <sys/stat.h> /* For mode constants */ #include <semaphore.h> #include <stdio.h> void print(sem_t *print1, sem_t *print2) { int i = 0; while(1) { sem_wait(print1); i++; printf("int print1 i = %d\n", i); sem_post(print2); } } int main(int argc, char **argv) { sem_t *print1, *print2; print1 = sem_open("sem_print1", O_CREAT, 0777, 0); if(SEM_FAILED == print1) { perror("sem_open"); } print2 = sem_open("sem_print2", O_CREAT, 0777, 1); if(SEM_FAILED == print2) { perror("sem_open"); } print(print1, print2); return 0; }
print2.c
#include <fcntl.h> /* For O_* constants */ #include <sys/stat.h> /* For mode constants */ #include <semaphore.h> #include <stdio.h> void print(sem_t *print1, sem_t *print2) { int i = 0; while(1) { sem_wait(print2); i++; printf("in print2 i = %d\n", i); sleep(1); sem_post(print1); } } int main(int argc, char **argv) { sem_t *print1, *print2; print1 = sem_open("sem_print1", O_CREAT, 0777, 0); if(SEM_FAILED == print1) { perror("sem_open"); } print2 = sem_open("sem_print2", O_CREAT, 0777, 1); if(SEM_FAILED == print2) { perror("sem_open"); } print(print1, print2); return 0; }
删除有名信号量示例代码如下：
#include <semaphore.h> #include <stdio.h> void sem_del(char *name) { int ret; ret = sem_unlink(name); if(ret < 0) { perror("sem_unlink"); } } int main(int argc, char **argv) { sem_del("sem_print1"); //删除信号量文件sem_print1 sem_del("sem_print2"); //删除信号量文件sem_print2 return 0; }
makefile 代码如下：
all: gcc sem_del.c -o sem_del -lpthread gcc print1.c -o print1 -lpthread gcc print2.c -o print2 -lpthread clean: rm sem_del print1 print2
运行程序时，先把有名信号量删除（sem_del），再分别运行 print1 和 print2
参考 https://www.cnblogs.com/jfyl1573/p/6820372.html
4）Shared Memory
write_shm.c
#include <sys/ipc.h> #include <sys/shm.h> #include <sys/types.h> #include <string.h> #include <stdio.h> #include <stdlib.h>
int main() { // 1. 创建 SHM int shm_id = shmget(13, 2048, IPC_CREAT | 0666); if (shm_id != -1) { // 2. 映射 SHM void* shm = shmat(shm_id, NULL, 0); if (shm != (void*)-1) { // 3. 写 SHM char str[] = "I'm share memory"; memcpy(shm, str, strlen(str) + 1); // 4. 关闭 SHM shmdt(shm); } else { perror("shmat:"); } } else { perror("shmget:"); } return 0; }
read_shm.c
#include <sys/ipc.h> #include <sys/shm.h> #include <sys/types.h> #include <string.h> #include <stdio.h> #include <stdlib.h> int main() { // 1. 获取 SHM int shm_id = shmget(13, 2048, IPC_CREAT | 0666); if (shm_id != -1) { // 2. 映射 SHM void* shm = shmat(shm_id, NULL, 0); if (shm != (void*)-1) { // 3. 读取 SHM char str[50] = { 0 }; memcpy(str, shm, strlen("I'm share memory")); printf("shm = %s\n", (char *)shm); // 4. 关闭 SHM shmdt(shm); } else { perror("shmat:"); } } else { perror("shmget:"); } if (0 == shmctl(shm_id, IPC_RMID)) printf("delete shm success.\n"); return 0; }
编译：
gcc write_shm.c -o write_shm
gcc read_shm.c -o read_shm
先运行写入 SHM：
./write_shm
再运行读取 SHM：
./read_shm
I'm share memory
成功读取了写进程的写入的数据，虽然不是同步的，但是至少能够获取数据。最后再来分析分析内核中的 SHM 调用过程吧。
参考：https://www.jianshu.com/p/494c2d32e3bb
#include <stdio.h> #include <stdlib.h> #include <sys/types.h> #include <sys/ipc.h> #include <sys/sem.h> #include <unistd.h> void init_sem(int , int ); void delete_sem(int ); void sem_p(int ); void sem_v(int ); union semun { int val; struct semid_ds *buf; unsigned short *array; }; void init_sem(int sem_id, int init_value) { union semun sem_union; sem_union.val = init_value; if (semctl(sem_id, 0, SETVAL, sem_union) < 0) { perror("failed to init_sem"); exit(-1); } return ; } void delete_sem(int sem_id) { union semun sem_union; if (semctl(sem_id, 0, IPC_RMID, sem_union) < 0) { perror("failed to delete_sem"); exit(-1); } return ; } void sem_p(int sem_id) { 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) < 0) { perror("failed to sem_p"); exit(-1); } return; } void sem_v(int sem_id) { 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) < 0) { perror("failed to sem_v"); exit(-1); } return ; }
#include <stdio.h> #include <stdlib.h> #include <string.h> #include <stdbool.h> #include <sys/types.h> #include <sys/ipc.h> #include <sys/shm.h> #include <errno.h> #include "sem.h" typedef struct { double lon; double lat; double bd_lon; double bd_lat; }gps_info_t; int main(int argc, const char *argv[]) { key_t key; int shmid; gps_info_t *gps = NULL; int create_flag = 0; int sem_id; if ((key = ftok(".", 'a')) < 0) { perror("failed to get key"); exit(-1); } if ((sem_id = semget(key, 1, 0666 | IPC_CREAT | IPC_EXCL)) < 0) { if (errno == EEXIST) { if ((sem_id = semget(key, 1, 0666)) < 0) { perror("failed to semget"); exit(-1); } } } init_sem(sem_id, 0); if ((shmid = shmget(key, sizeof(gps_info_t), 0666 | IPC_CREAT | IPC_EXCL)) < 0) { if (errno == EEXIST) { if ((shmid = shmget(key, sizeof(gps_info_t), 0666)) < 0) { perror("failed to create share memory"); exit(-1); } } else { perror("failed to shmget"); exit(-1); } } else create_flag = 1; if ((gps = shmat(shmid, NULL, 0)) == (void *)(-1)) { perror("failed to shmat"); exit(-1); } while(1) { sem_p(sem_id); printf("recv lon: %f\n", gps->lon); printf("recv lat: %f\n", gps->lat); sleep(1); } if (create_flag == 1) { if (shmdt(gps) < 0) { perror("failed to shmdt"); exit(-1); } if (shmctl(shmid, IPC_RMID, NULL) == -1) { perror("failed to delete share memory"); exit(-1); } delete_sem(sem_id); } return 0; }
write.c
#include <stdio.h> #include <stdlib.h> #include <string.h> #include <stdbool.h> #include <sys/types.h> #include <sys/ipc.h> #include <sys/shm.h> #include <errno.h> #include "sem.h" typedef struct { double lon; double lat; }gps_info_t; int main(int argc, const char *argv[]) { key_t key; gps_info_t *gps = NULL; int shmid; int create_flag = 0; int sem_id; if ((key = ftok(".", 'a')) < 0) { perror("failed to get key"); exit(-1); } if ((sem_id = semget(key, 1, 0666 | IPC_CREAT | IPC_EXCL)) < 0) { if (errno == EEXIST) { if ((sem_id = semget(key, 1, 0666)) < 0) { perror("failed to semget"); exit(-1); } } } init_sem(sem_id, 0); if ((shmid = shmget(key, sizeof(gps_info_t), 0666 | IPC_CREAT | IPC_EXCL)) < 0) { if (errno == EEXIST) { if ((shmid = shmget(key, sizeof(gps_info_t), 0666)) < 0) { perror("failed to shmget memory"); exit(-1); } } else { perror("failed to shmget"); exit(-1); } } else create_flag = 1; if ((gps = shmat(shmid, NULL, 0)) == (void *)(-1)) { perror("failed to shmat memory"); exit(-1); } while(1) { gps->lon += 1.1; gps->lat += 2.2; printf("send lon: %f\n", gps->lon); printf("send lat: %f\n", gps->lat); sem_v(sem_id); sleep(2); } if (create_flag == 1) { if (shmdt(gps) < 0) { perror("failed to shmdt memory"); exit(-1); } if (shmctl(shmid, IPC_RMID, NULL) == -1) { perror("failed to delete share memory"); exit(-1); } delete_sem(sem_id); } return 0; }
Makefile
OBJ= write read
all: ${OBJ}
read:
gcc -g -o read read.c
write:
gcc -g -o write write.c
clean:
rm -f ${OBJ}
.PHONY: ${OBJ}
linux its
1) semaphore
#include <stdio.h> #include <stdlib.h> #include <semaphore.h> #include <pthread.h> #define err_sys(msg) \ do { perror(msg); exit(-1); } while(0) #define err_exit(msg) \ do { fprintf(stderr, msg); exit(-1); } while(0) void *r1(void *arg) { sem_t* sems = (sem_t *)arg; static int cnt = 10; while(cnt--) { sem_wait(sems); printf("I am in r1. I get the sems.\n"); } } void *r2(void *arg) { sem_t* sems = (sem_t *)arg; static int cnt = 10; while(cnt--) { printf("I am in r2. I send the sems\n"); sem_post(sems); sleep(1); } } int main(void) { sem_t sems; pthread_t t1, t2; printf("sems size: %d\n", sizeof(sems)); /* sem_init()第二个参数为0表示这个信号量是当前进程的局部信号量，否则该信号 * 就可以在多个进程之间共享 */ if(sem_init(&sems, 0, 0) < 0) err_sys("sem_init error"); pthread_create(&t1, NULL, r1, &sems); pthread_create(&t2, NULL, r2, &sems); pthread_join(t1, NULL); pthread_join(t2, NULL); sem_destroy(&sems); return 0; }
gcc -o pthread_sem_demo pthread_sem_demo.c -pthread
./pthread_sem_demo
参考 http://blog.csdn.net/u012796139/article/details/46743677
3) Linux 线程挂起与唤醒功能 实例
https://blog.csdn.net/waldmer/article/details/23422943
https://www.cnblogs.com/noaming1900/archive/2011/01/14/1935526.html
1）Linux下进程通信方式（共享内存，管道，消息队列，Socket）
https://www.cnblogs.com/lou424/p/5018966.html
2）Compare performance of IPC(Inter-Process Communication), include file, zeromq, socket, unixsocket, share-memory, msq-queue and so on
https://github.com/zhiyuan2007/IPC-performance-compare
3）linux线程间同步(Inter-Thread Synchronization)方式汇总
https://github.com/clpsz/linux-itss
linux ipc 扫盲
https://www.ibm.com/developerworks/cn/linux/l-ipc/
