标签：ipc
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
int msgget(key_t key, int msgflg); struct msqid_ds {
struct ipc_perm msg_perm; /* Ownership and permissions */
time_t msg_stime; /* Time of last msgsnd(2) */
time_t msg_rtime; /* Time of last msgrcv(2) */
time_t msg_ctime; /* Time of last change */
unsigned long __msg_cbytes; /* Current number of bytes in
queue (nonstandard) */
msgqnum_t msg_qnum; /* Current number of messages
in queue */
msglen_t msg_qbytes; /* Maximum number of bytes
allowed in queue */
pid_t msg_lspid; /* PID of last msgsnd(2) */
pid_t msg_lrpid; /* PID of last msgrcv(2) */
}; struct ipc_perm {
key_t __key; /* Key supplied to msgget(2) */
uid_t uid; /* Effective UID of owner */
gid_t gid; /* Effective GID of owner */
uid_t cuid; /* Effective UID of creator */
gid_t cgid; /* Effective GID of creator */
unsigned short mode; /* Permissions */
unsigned short __seq; /* Sequence number */
}; #include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
int msgsnd(int msqid, const void *msgp, size_t msgsz, int msgflg); struct msgbuf {
long mtype; /* message type, must be > 0 */
char mtext[1]; /* message data */
}; #include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
ssize_t msgrcv(int msqid, void *msgp, size_t msgsz, long msgtyp, int msgflg);#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <errno.h>
#include <unistd.h>
#include <signal.h>
#include <stdlib.h>
#include "slnmq.h"
static int recv_type, msgid;
int sln_server_loop(void)
{
int rcvmsg_len;
key_t key;
struct sln_msgbuf slnmsg;
key = ftok(SLN_IPC_MQ_NAME, 0);
if (key < 0) {
fprintf(stderr, "ftok: %s\n", strerror(errno));
return -1;
}
msgid = msgget(key, IPC_CREAT | IPC_EXCL);
if ((msgid < 0) && (errno != EEXIST)) {
fprintf(stderr, "msgget: %s\n", strerror(errno));
return -1;
}
if (msgid < 0) {
printf("Open existing mq!\n");
msgid = msgget(key, IPC_CREAT);
if (msgid < 0) {
fprintf(stderr, "msgget: %s\n", strerror(errno));
return -1;
}
}
sleep(10); //just for test
for (;;) {
rcvmsg_len = msgrcv(msgid, &slnmsg, SLN_IPC_MQ_MSGSIZE, recv_type, 0);
if (rcvmsg_len < 0) {
fprintf(stderr, "msgrcv: %s\n", strerror(errno));
sleep(1);
continue;
}
fprintf(stdout, "receive - recv len: %d, msg type: %d, msg: %s\n",
rcvmsg_len, slnmsg.msgtype, slnmsg.msg);
}
return 0;
}
static void sigint_func(int sig)
{
if (msgctl(msgid, IPC_RMID, NULL) < 0) {
fprintf(stderr, "msgctl: %s\n", strerror(errno));
}
exit(0);
}
int main(int argc, const char *argv[])
{
FILE *fp = NULL;
if (argc != 2) {
fprintf(stderr, "Usage: %s <msg type>\n", argv[0]);//运行时，指定服务要进程接收的消息类型
return -1;
}
recv_type = atoi(argv[1]);
if (access(SLN_IPC_MQ_NAME, F_OK) < 0) {
fp = fopen(SLN_IPC_MQ_NAME, "w+");
if (NULL != fp) {
fclose(fp);
}
}
signal(SIGINT, sigint_func); //服务进程捕获中断信号，在中断处理函数里面删除消息队列并推出程序
sln_server_loop();
return 0;
}#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <errno.h>
#include "slnmq.h"
int sln_msgsnd(int msg_type, const void *sndmsg, int sndlen)
{
int msgid, rcvmsg_len;
key_t key;
struct sln_msgbuf slnmsg;
key = ftok(SLN_IPC_MQ_NAME, 0);
if (key < 0) {
fprintf(stderr, "ftok: %s\n", strerror(errno));
return -1;
}
msgid = msgget(key, IPC_CREAT);
if (msgid < 0) {
fprintf(stderr, "msgget: %s\n", strerror(errno));
return -1;
}
slnmsg.msgtype = msg_type;
memcpy(&slnmsg.msg, sndmsg, sndlen);
msgsnd(msgid, (void *)&slnmsg, sndlen, 0);
}
int main(int argc, const char *argv[])
{
int type;
if (argc != 3) {
fprintf(stderr, "Usage: %s <msg type> <msg content>\n", argv[0]);
return -1;
}
type = atoi(argv[1]);
sln_msgsnd(type, argv[2], strlen(argv[2]) + 1);
return 0;
}./client 1 abcd ./client 2 efghi ./client 3 jkl ./client 4 mn ./client 5 opqrst ./client 6 uv ./client 7 w ./client 8 xyz
# ./server 0（读取所有消息） receive - recv len: 5, msg type: 1, msg: abcd receive - recv len: 6, msg type: 2, msg: efghi receive - recv len: 4, msg type: 3, msg: jkl receive - recv len: 3, msg type: 4, msg: mn receive - recv len: 7, msg type: 5, msg: opqrst receive - recv len: 3, msg type: 6, msg: uv receive - recv len: 2, msg type: 7, msg: w receive - recv len: 4, msg type: 8, msg: xyz
# ./server 4 （读取消息类型为4的消息） Open existing mq! receive - recv len: 3, msg type: 4, msg: mn
# ./server -5 （读取消息小于5的消息） Open existing mq! receive - recv len: 5, msg type: 1, msg: abcd receive - recv len: 6, msg type: 2, msg: efghi receive - recv len: 4, msg type: 3, msg: jkl receive - recv len: 3, msg type: 4, msg: mn receive - recv len: 7, msg type: 5, msg: opqrst
# ipcs ------ Message Queues -------- key msqid owner perms used-bytes messages 0x001fffde 229376 root 0 0 0
# ipcs ------ Message Queues -------- key msqid owner perms used-bytes messages
标签：ipc
原文地址：http://blog.csdn.net/shallnet/article/details/41806415
