Can't fprintf with SIGEV_PULSE

QNX DEVELOPERS General Programming
1

Hi all,

I’m trying to log local computer time periodically into a file.
When I run the program, my time.txt file has nothing in it.

I’ve written the code to retrive the local computer time.
Here is part of my code:


#define OneMilliSec 1000000

FILE *myfile1;

typedef union{
   struct _pulse pulse;
} my_message_t;

int main (void){

...

initTimer();
myfile1 = fopen("/root/time.txt");

while(1){
   rcvid = MsgReceive(chid, &msg, sizeof(msg), NULL);
   if (rcvid == 0){
     fprintf(myfile1, "%d %d %d\n", Hour, Min, Sec);

      ...

   }
}

void initTimer(void){
   struct sigevent event;
   struct itimerspec itime;

   timer _t timer_id;

   chid = ChannelCreate (0);

   event.sigev_notify = SIGEV_PULSE;
   event.sigev_coid = ConnectAttach(ND_LOCAL_NODE, 0, chid, _NTO_SIDE_CHANNEL, 0);
   event.sigve_proprity = getprio(0);

   timer_create(CLOCK_REALTIME, &event, &timer_id);

   itime.it_value.tv_sec = 0;
   itime.it_value.tv_nsec = 10 * OneMilliSec;
   itime.it_interval.tv_sec = 0;
   itime.it_interval.tv_nsec = 10 * OneMilliSec;
   timer_settime(timer_id, 0, &itimer, NULL);
}

If I comment off the MsgReceive line, etc:

   //rcvid = MsgReceive(chid, &msg, sizeof(msg), NULL);

I’m able to log the time but it is not at interval of 10ms.
It is logged continuously as fast as the computer can.

What changes must I make in order to log the time at the specific interval?
Or are there better ways to do it?

Thanks for helping.

Rabbit

2

ALWAYS check the return value of thinks like ChannelCreate, ConnectAttach, timer_create, timer_settime, and on error check the value of errno.

3

It’s pretty hard to know what is wrong since you clearly didn’t
give us real code. The above would have compiler errors even
if the missing code was not. I redid your code below, and it works
as expected.

#include <libc.h>
#include <sys/neutrino.h>
#include <sys/netmgr.h>

FILE *myfile1; 
int chid;
typedef union
{ 
	struct _pulse pulse; 
} my_message_t; 

void initTimer(void);
int main (void)
{ 
	int rcvid;
	char msg[80];

	initTimer(); 
	myfile1 = stderr; 

	while(1)
	{ 
		rcvid = MsgReceive(chid, &msg, sizeof(msg), NULL); 
		if (rcvid == 0)
		{ 
			fprintf(myfile1, "Got Pulse\n"); 
		}
	} 
} 

void initTimer(void)
{ 
	struct sigevent event; 
	struct itimerspec itime; 

	timer_t timer_id; 

	chid = ChannelCreate(0); 

	event.sigev_notify = SIGEV_PULSE; 
	event.sigev_coid = ConnectAttach(ND_LOCAL_NODE, 0, chid, _NTO_SIDE_CHANNEL, 0); 
	event.sigev_priority = getprio(0); 

	timer_create(CLOCK_REALTIME, &event, &timer_id); 

	itime.it_value.tv_sec = 1; 
	itime.it_value.tv_nsec = 0;
	itime.it_interval.tv_sec = 1; 
	itime.it_interval.tv_nsec = 0; 
	timer_settime(timer_id, 0, &itime, NULL); 
}
4

Hi mario and maschoen.

I can logged data after I restart QNX without changing any codes.
Guess there is something wrong with QNX while I’m programming.

Thanks for replying. =)

5

99% of the time the problem is not the OS, but the person sitting in front of it ;-)

6

Mario, that depends on the OS ;-). A certain prevelant OS I have to use from time to
time does non-repeatable nasty things all the time.

7

This is a QNX forum right ;-)