Linux 进程间通信(一)

 1 #include <stdio.h>
 2 #include <sys/msg.h>
 3 #include <sys/types.h>
 4 #include <sys/ipc.h>
 5 
 6 int main()
 7 {
 8     int msgid;
 9     
10     //通过这样可以避免标识符的重复
11     //key_t myKey;
12     //myKey = ftok("/home/queues/myqueue", 0);
13 
14     msgid = msgget( 0x111, IPC_CREAT|0666);
15     if(msgid >= 0)
16         printf("Created a Msg Queue %d\n", msgid);
17         
18     return 0;
19 }
20 
21 创建消息队列

 1 #include <stdio.h>
 2 #include <sys/msg.h>
 3 #include <sys/types.h>
 4 
 5 int main(int argc, char **argv)
 6 {
 7     int msgid, ret;
 8     struct msqid_ds buf;
 9     
10     //获取消息队列
11     msgid = msgget(0x111, 0);
12     
13     if(msgid >= 0){
14         ret = msgctl(msgid, IPC_STAT, &buf);
15         buf.msg_qbytes = 4096;
16         
17         ret = msgctl(msgid, IPC_SET, &buf);
18         
19         if(ret == 0){
20             printf("change queue size success");
21         }
22     }
23     
24     return 0;
25 }

 1 #include <stdio.h>
 2 #include <sys/msg.h>
 3 #include <sys/types.h>
 4 #include <string.h>
 5 
 6 typedef struct{
 7     long type;
 8     float fval;
 9     unsigned int unival;
10     char message[1024];
11 }myType;
12 
13 int main()
14 {
15     myType msg;
16     int qid,ret;
17     
18     qid = msgget(0x111, 0);
19     if(qid > 0){
20         msg.type = 1L;
21         msg.fval = 123.456;
22         msg.unival = 256;
23         strcpy( msg.message, "this is a msg in queue\n");
24         
25         ret = msgsnd(qid, (struct msgbuf*)&msg, sizeof(myType), 0);
26         if(ret != -1)
27             printf("sent success!\n");
28     }
29     
30     return 0;
31 }

 1 #include <stdio.h>
 2 #include <sys/msg.h>
 3 #include <sys/types.h>
 4 #include <string.h>
 5 
 6 typedef struct{
 7     long type;
 8     float fval;
 9     unsigned int unival;
10     char message[1024];
11 }myType;
12 
13 int main()
14 {
15     myType msg;
16     int qid,ret;
17     
18     qid = msgget(0x111, 0);
19     if(qid >= 0){
20         
21         ret = msgsnd(qid, (struct msgbuf*)&msg, sizeof(myType), 0);
22         if(ret != -1)
23             printf("recv success!\n");
24             printf("type : %ld\n", msg.type);
25             printf("float value: %f\n", msg.fval);
26             printf("Unit value: %d\n", msg.unival);
27             printf("String value: %s\n", msg.message);
28     }
29     
30     return 0;
31 }

 1 #include <stdio.h>
 2 #include <sys/ipc.h>
 3 #include <sys/shm.h>
 4 
 5 int main()
 6 {
 7     int shmid;
 8     
 9     shmid = shmget( 0x123, 4096, IPC_CREAT|0666);
10     if(shmid >= 0)
11         printf("Created a shared memory %d\n", shmid);
12         
13     return 0;
14 }

 1 #include <stdio.h>
 2 #include <sys/shm.h>
 3 #include <errno.h>
 4 #include <sys/ipc.h>
 5 #include <sys/types.h>
 6 
 7 int main(int argc, char **argv)
 8 {
 9     int shmid, ret;
10     struct shmid_ds shmds;
11     
12     //获取共享内存
13     shmid = shmget(0x123, 0, 0);
14     
15     if(shmid >= 0){
16         ret = shmctl(shmid, IPC_STAT, &shmds);
17         if(ret == 0){
18             printf("shared memory size : %d/n", shmds.shm_segsz);
19             printf("attaches number: %d/n", (int)shmds.shm_nattch);
20         }else
21             printf("shmctl error!\n");
22     }else
23         printf("shared memory not found!\n");
24     
25     return 0;
26 }

 1 #include <stdio.h>
 2 #include <sys/shm.h>
 3 #include <errno.h>
 4 #include <sys/ipc.h>
 5 #include <sys/types.h>
 6 #include <string.h>
 7 
 8 int main(int argc, char **argv)
 9 {
10     int shmid, ret;
11     void* mem;
12     
13     //获取共享内存
14     shmid = shmget(0x123, 0, 0);
15     
16     if(shmid >= 0){
17         
18         mem = shmat( shmid, (const void*)0, 0 );
19         
20         strcpy((char*)mem, "This is a shared memory\n");
21         
22         ret = shmdt(mem);
23         
24     }else
25         printf("shared memory not found!\n");
26     
27     return 0;
28 }

 1 #include <stdio.h>
 2 #include <sys/shm.h>
 3 #include <errno.h>
 4 #include <sys/ipc.h>
 5 #include <sys/types.h>
 6 #include <string.h>
 7 
 8 int main(int argc, char **argv)
 9 {
10     int shmid, ret;
11     void* mem;
12     
13     //获取共享内存
14     shmid = shmget(0x123, 0, 0);
15     
16     if(shmid >= 0){
17         
18         mem = shmat( shmid, (const void*)0, 0 );
19         
20         printf("%s", (char*)mem);
21         
22         ret = shmdt(mem);
23         
24     }else
25         printf("shared memory not found!\n");
26     
27     return 0;
28 }

 1 #include <stdio.h>
 2 #include <sys/shm.h>
 3 #include <errno.h>
 4 #include <sys/ipc.h>
 5 #include <sys/types.h>
 6 
 7 int main(int argc, char **argv)
 8 {
 9     int shmid, ret;
10     
11     //获取共享内存
12     shmid = shmget(0x123, 0, 0);
13     
14     if(shmid >= 0){
15         ret = shmctl(shmid, IPC_RMID, 0);
16         if(ret == 0){
17             printf("shared memory removed!");
18         }else
19             printf("shmctl error!\n");
20     }else
21         printf("shared memory not found!\n");
22     
23     return 0;
24 }