From mboxrd@z Thu Jan  1 00:00:00 1970
From: NZG <ngustavson@domain.hid>
Date: Thu, 7 Jun 2007 14:13:10 -0500
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Subject: Re: [Xenomai-help] writing from NRT to a rt_pipe
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To: xenomai@xenomai.org

Further experimentations appear to show that the problem is that I'm closing 
the NRT pipe before data is received in the RT thread, this appears to cause 
the loss of data in the pipe.

Is this the desired behavior?

NZG


On Thursday 07 June 2007 1:57 pm, NZG wrote:
> When writing from NRT to a real time pile (open, write, close).
> Are message boundaries preserved based upon the length of the write call?
>
> It's not working for me. The code below returns success, but calling
>
> err = rt_pipe_read(comp,k,sizeof(kommand_t),TM_NONBLOCK);
> or
> err = rt_pipe_read(comp,k,sizeof(kommand_t),100);
>
> from RT space on the same pipe never returns any data
>
> err = rt_pipe_read(comp,k,sizeof(kommand_t),TM_NONBLOCK);
> always returns err
> 0x0b,  Resource temporarily unavailable
>
>  err = rt_pipe_read(comp,k,sizeof(kommand_t),100);
> always returns err:
> 0x6e, Connection timed out
>
> NZG
>
> code specifics follow...............
>
> 		int err;
> 		kommand_t k = {
> 		.type = KILLCYCLE,
> 		};
>
> 	    int cfd = open(COMMANDPIPE, O_WRONLY|O_SYNC);
>
> 	   if(cfd<0){
> 	   	printf("can't open %s (%s)\n",COMMANDPIPE, strerror(-cfd));
> 	   	fflush(stdout);
> 	   	return;
> 	   }
>
> 	   printf("sizeof kommand_t = %u\n",sizeof(kommand_t));
>
>        err=write(cfd,&k,sizeof(kommand_t));
>
>        if(err>=0)printf("wrote %u bytes to %s\n",err,COMMANDPIPE);
>
>        if(err<0)printf("err writing to %s (%s)\n",COMMANDPIPE,
> strerror(errno));
>
>
>        if(close(cfd)<0)printf("couldn't close %s\n",COMMANDPIPE);
>
>
>
>
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