int
main(int argc, char **argv)
{
int c, flags;
mqd_t mqd;
ssize_t n;
uint32_t prio;
void *buff;
struct mq_attr attr;
flags = O_RDONLY;
while ( (c = Getopt(argc, argv, "n")) != -1) {
switch (c) {
case 'n':
flags |= O_NONBLOCK;
break;
}
}
if (optind != argc - 1)
err_quit("usage: mqreceive [ -n ] <name>");
mqd = Mq_open(argv[optind], flags);
Mq_getattr(mqd, &attr); // get the max msg size for alloc memory..
buff = Malloc(attr.mq_msgsize);
n = Mq_receive(mqd, buff, attr.mq_msgsize, &prio);
printf("read %ld bytes, priority = %u\n", (long) n, prio);
exit(0);
}
static void sig_usr1(int signo)
{
ssize_t n;
Mq_notify(mqd, &sigev);
n = Mq_receive(mqd, buff, attr.mq_msgsize, NULL);
printf("SIGUSR1 received, read %ld bytes\n", (long)n);
return;
}
void
doit(mqd_t mqsend, mqd_t mqrecv)
{
char buff[MSGSIZE];
Mq_send(mqsend, buff, 1, 0);
if (Mq_receive(mqrecv, buff, MSGSIZE, NULL) != 1)
err_quit("mq_receive error");
}
/*
* =====================================================================
* Function:MsgQReceive()
* Description: receive a message from a message queue
* Input: msgQId -- msgQ id
* recvBuffer -- buffer to save message
* bufLength -- length of recvBuffer
* timeTick -- wait time (in ticks)
* WAIT_FOREVER, this routine block until message available
* NO_WAIT, this routine return immediately with errorno
* wait time, this routine block until message available or time up
* Output: N/A
* Return: OK on success or ERROR otherwise.
*======================================================================
*/
int MsgQReceive(MSG_QUEUE_ID msgQId, char* recvBuffer, int bufLength, int timeTick)
{
#ifdef LINUX_OS
if (msgQId == AII_NULL || recvBuffer == AII_NULL)
{
return (-1);
}
return Mq_receive((mqd_t)(*msgQId), recvBuffer, bufLength, timeTick, AII_NULL);
#elif VXWORKS_OS
if (msgQId == AII_NULL || recvBuffer == AII_NULL)
{
return (-1);
}
return msgQReceive(msgQId, recvBuffer, bufLength, timeTick);
#endif
}
int
main(int argc, char **argv)
{
mqd_t mqd;
void *buff;
ssize_t n;
sigset_t zeromask, newmask, oldmask;
struct mq_attr attr;
struct sigevent sigev;
if (argc != 2)
err_quit("usage: mqnotifysig2 <name>");
/* 4open queue, get attributes, allocate read buffer */
mqd = Mq_open(argv[1], O_RDONLY);
Mq_getattr(mqd, &attr);
buff = Malloc(attr.mq_msgsize);
Sigemptyset(&zeromask); /* no signals blocked */
Sigemptyset(&newmask);
Sigemptyset(&oldmask);
Sigaddset(&newmask, SIGUSR1);
/* 4establish signal handler, enable notification */
Signal(SIGUSR1, sig_usr1);
sigev.sigev_notify = SIGEV_SIGNAL;
sigev.sigev_signo = SIGUSR1;
Mq_notify(mqd, &sigev);
for ( ; ; ) {
Sigprocmask(SIG_BLOCK, &newmask, &oldmask); /* block SIGUSR1 */
while (mqflag == 0)
sigsuspend(&zeromask);
mqflag = 0; /* reset flag */
Mq_notify(mqd, &sigev); /* reregister first */
n = Mq_receive(mqd, buff, attr.mq_msgsize, NULL);
printf("read %ld bytes\n", (long) n);
Sigprocmask(SIG_UNBLOCK, &newmask, NULL); /* unblock SIGUSR1 */
}
exit(0);
}
int
main(int argc, char **argv)
{
int i, nloop;
mqd_t mq1, mq2;
char buff[MSGSIZE];
pid_t childpid;
struct mq_attr attr;
if (argc != 2)
err_quit("usage: lat_pxmsg <#loops>");
nloop = atoi(argv[1]);
attr.mq_maxmsg = MAXMSG;
attr.mq_msgsize = MSGSIZE;
mq1 = Mq_open(Px_ipc_name(NAME1), O_RDWR | O_CREAT, FILE_MODE, &attr);
mq2 = Mq_open(Px_ipc_name(NAME2), O_RDWR | O_CREAT, FILE_MODE, &attr);
if ( (childpid = Fork()) == 0) {
for ( ; ; ) { /* child */
if (Mq_receive(mq1, buff, MSGSIZE, NULL) != 1)
err_quit("mq_receive error");
Mq_send(mq2, buff, 1, 0);
}
exit(0);
}
/* 4parent */
doit(mq1, mq2);
Start_time();
for (i = 0; i < nloop; i++)
doit(mq1, mq2);
printf("latency: %.3f usec\n", Stop_time() / nloop);
Kill(childpid, SIGTERM);
Mq_close(mq1);
Mq_close(mq2);
Mq_unlink(Px_ipc_name(NAME1));
Mq_unlink(Px_ipc_name(NAME2));
exit(0);
}
