摘要：
msgget()函数被用来创建新的消息队列或获取已有的消息队列。其函数定义如下：系统调用： msgget()函数声明： int msgget ( key_t key, int msgflg )返回值： message queue identifier on success-1 on error: errno = EACCESS (permission denied)EEXIST (Queue exists, cannot create)EIDRM (Queue is marked for deletion)ENOENT (Queue does not exist)ENOMEM (Not eno 阅读全文
摘要：
msgrcv()函数被用来从消息队列中取出消息。它在linux/msg.h中的定义是这样的：系统调用： msgrcv()函数声明： int msgrcv ( int msqid, struct msgbuf *msgp, int msgsz, longmtype,int msgflg )返回值： Number of bytes copied into message buffer-1 on error: errno = E2BIG (Message length is greater thanmsgsz,no MSG_NOERROR)EACCES (No read permission)EFA 阅读全文
摘要：
msgsnd()函数是用来向消息队列发送消息的。在linux/msg.h 它的函数定义是这样的：系统调用： msgsnd()函数声明： int msgsnd ( int msqid, struct msgbuf *msgp, int msgsz, int msgflg )返回值： 0 on success-1 on error: errno = EAGAIN (queue is full, and IPC_NOWAIT was asserted)EACCES (permission denied, no write permission)EFAULT (msgp address isn' 阅读全文