Problems using pulses !!!

QNX DEVELOPERS General Programming
1

Hi Community!!!

How is it possible to change the source code, that two or more pulses can be send.

Like in QNX4 with “trigger (proxy)”

Thank You !!!

---------------------------HEADER FILE---------------------------------
struct my_msg
{
short type;
char string[200]; /Message/
struct sigevent event;
};

#define MY_PULSE_CODE _PULSE_CODE_MINAVAIL+5
#define MSG_GIVE_PULSE _IO_MAX+4

/find server/
#define ATTACH_POINT “a”

------------------------SOURCE-----------------------------------------

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <sys/neutrino.h>
#include <sys/iomsg.h>
#include <sys/dispatch.h>

#include “my_hdr.h”
int main( int argc, char **argv)
{

struct my_msg msg;
struct _pulse pulse;

int rcvid,chid, coid, srv_coid;
name_attach_t *attach;
pid_t npid;

npid=fork();

if(npid){ // SERVER

		 /* attach the name the client will use to find us */
		  /* our channel will be in the attach structure */
		  if ( (attach = name_attach( NULL, ATTACH_POINT, 0 )) == NULL)
		{
		 printf("SERVER: failed to attach name, errno %d\n", errno );
			 exit(1);
		 }

		 /* wait for the message from the client */
		 rcvid = MsgReceive(attach->chid, &msg, sizeof( msg ), NULL );
		 
		 printf("DIE RCVID IST: %d\n",rcvid);
		 
		 if ( msg.type == MSG_GIVE_PULSE )
			 { 
			  /* wait until it is time to notify the client */
 				sleep(2);

				 /* deliver notification to client that client requested */
			 	MsgDeliverEvent( rcvid, &msg.event );
		  		printf("SERVER: delivered event\n");
		  		printf("SERVER :  Der inhalt des PULSES war:  %s\n",msg.string);
		} else

{
printf(“SERVER: unexpected message \n”);
}
return 0;

}else{ // CLIENT

	strcpy(msg.string,"PULSE PULSE PULSE PULSE "); 
	  
	 /* we need a channel to receive the pulse notification on */
	 chid = ChannelCreate( 0 ); 

	  /* and we need a connection to that channel for the pulse to be
	  delivered on */
	  
	  /*If flags contains _NTO_COF_CLOEXEC, the connection is closed
  		when your process calls an exec*() function to start a new process*/
	 coid = ConnectAttach( 0, 0, chid, _NTO_SIDE_CHANNEL, 0 );

	 /* fill in the event structure for a pulse (to send a pulse).*/
	 /*SIGEV_PULSE_INIT( event, coid, priority, code, value )*/
	 SIGEV_PULSE_INIT( &msg.event, coid, SIGEV_PULSE_PRIO_INHERIT, 
                MY_PULSE_CODE, 0 );
                
	 msg.type = MSG_GIVE_PULSE; /*"my_hdr.h" */

	 /* find the server */
	 if ( (srv_coid = name_open( ATTACH_POINT, 0 )) == -1)
	 {
		 printf("CLIENT: failed to find server, errno %d\n", errno );
 		 exit(1);
	 }

	  /* give the pulse event we initialized above to the server for
		 later delivery */
	 MsgSend( srv_coid, &msg, sizeof(msg), NULL, 0 );

	/* wait for the pulse from the server */
	 rcvid = MsgReceivePulse( chid, &pulse, sizeof( pulse ), NULL );
	
	
	printf("CLIENT: Receive Code %d waiting for %d  \n",
	pulse.code, MY_PULSE_CODE );

	return 0;
  }

}

2

What exactly about the code you provided do you think isn’t working ?

Obviously, in order to receive additional pulses you can’t exit() after receiving one, so I need clarification on what you are trying to do ?

Rennie

3

Thank you Renni !
I would like to use Pulses to send two or more messages from process A to process B.
Like as a Notification of something who is ready

struct msg1 {
short unsigned type;
char string [ZMAX];
};

union {
short unsigned type;
struct msg1 send_value;
} msg;

int main(void)
{
pid_t npid, proxy;

int i , flag=0;

msg.type = MSG_CODE;

strcpy(msg.send_value.string," Message");

proxy = qnx_proxy_attach(0,&msg.send_value,sizeof(msg.send_value),-1);

if (proxy == -1) {
printf (“No Proxy (%s)!\n”,strerror(errno));
return 2;
}
npid = fork() ;

if (npid) {

for ( i=1;i<=2;i++) { /* 2 Messages */

    printf ("Parent: Wait 2s ...\n");
    sleep(2) ;
    printf ("Parent: Receive \n");
    npid = Receive(0,&msg,sizeof(msg));
    
    if (npid != -1) {
             
             if (msg.type == MSG_CODE) {
                printf ("Parent: The Message:\n%s\n", msg.send_value.string);
             }else{
                printf ("Parent wrong Type of Message %d \n",msg.type);
                break;
             }
    }
}

printf (“Parent: EXIT\n”);
return 0;

} else {

Trigger(proxy);/Send Proxy/
printf (" Proxy Trigger\n");
printf (“Wait 3s …\n”);
sleep(3) ;
Trigger(proxy);
printf (" Proxy trigger new\n");
printf (“EXIT\n”);

return 0;
}