Ok, Thanx.  I'll make the changes.

-----Original Message-----
From: David Sarrazin [mailto:community-noreply@qnx.com] 
Sent: Tuesday, September 09, 2008 2:51 PM
To: ostech-core_os
Subject: RE: ConnectAttach fails connecting to a daemon

Only the owner of a channel (ie, the process who called ChannelCreate())
can receive messages/pulses on it.  A channel is not needed to send,
only to receive.  Yes, Process A will have to know the PID and CHID of
process B, in order to send it a message.  Process A  only needs to call
ChannelCreate() if it wants to receive messages itself.  FYI process A
and Process B need to send messages one direction, not both (ie. A->B
OR B->A, don't have A<->B), as you can get a deadlock if they send to
each other.

As for how to get the chid out of process B?  There are several methods:
a shared memory region; printing the chid on the console, and passing it
as a cmd-line arg to process A; resmgr_attach() and it's associated
functions (note this is a more involved method, but great if you plan
for your processes to register pathnames, and respond to all the
"normal" POSIX operations).

David

> -----Original Message-----
> From: Tim Gessner [mailto:community-noreply@qnx.com] 
> Sent: September 9, 2008 5:36 PM
> To: ostech-core_os
> Subject: RE: ConnectAttach fails connecting to a daemon
> 
> Interesting, that is not how I read the documentation.  Since 
> I can't know the channel of Proc B in Proc A - it is a FD 
> created by the call to ChannelCreate in Proc B, there is no 
> way to connect from Proc A if the ChId is created in Proc B.  
> As I understood the documentation Proc B calls ChannelCreate 
> and Proc A calls ChannelCreate.  The ChId passed into 
> ConnectAttach in Proc A is the channel created by Proc A.
> 
> Am I still misunderstanding this?
> 
> Thanx
> Tim
> 
> 
> 
> -----Original Message-----
> From: Shiv Nagarajan [mailto:community-noreply@qnx.com]
> Sent: Tuesday, September 09, 2008 2:25 PM
> To: ostech-core_os
> Subject: Re: ConnectAttach fails connecting to a daemon
> 
> So if process A is looking for proc B's pid, it should be 
> connecting to proc B's channel, not creating a channel and 
> connecting to it.
> 
> the nd, pid, chid being passed to the connectattach, refer to 
> the owner of the channel.
> 
> so in your call 
> 
> 
> int nCoID = ::ConnectAttach(ND_LOCAL_NODE,tPID,nChID,0 |
>     _NTO_SIDE_CHANNEL,0);
> 
> should really be
> 
> In Proc A
> 
> ProcBpid = query for proc B pid
> ProcBChid = proc B's channel
> 
> int nCoID = ::ConnectAttach(ND_LOCAL_NODE,ProcBPid,ProcBChid,0 |
>     _NTO_SIDE_CHANNEL,0);
> 
> shiv
> Tue Sep  9 17:23:57 EDT 2008
> 
>  --> According to Tim Gessner <--
> 	Yes there is a server and a client and they are both daemons.
> Proc A
> 	gets an event and querys for Proc B's PID.  Proc A then calls
> 	ChannelCreate and ConnectAttach to connect to Proc B.  
> Proc A then sends
> 	a message to Proc B.  The code snippet I just sent was 
> from Proc A, the
> 	process which is trying to connect.  The code to create 
> the daemons is
> 	identical other than the printf messages they display, "Server
> 	starting... " "Client Starting..." and the class that 
> is created CServer
> 	CClient, etc.
> 	
> 	Does that make sense?  Essentially I have two daemons 
> which both access
> 	shared memory.  They communicate to each other (when 
> necessary) through
> 	messages.
> 	
> 	Thanx
> 	Tim
> 	
> 	-----Original Message-----
> 	From: Shiv Nagarajan [mailto:community-noreply@qnx.com] 
> 	Sent: Tuesday, September 09, 2008 2:14 PM
> 	To: ostech-core_os
> 	Subject: Re: ConnectAttach fails connecting to a...

thanks dave.. couldn't have described it any better :)

shiv
Tue Sep  9 18:21:53 EDT 2008

 --> According to David Sarrazin <--
	Only the owner of a channel (ie, the process who called ChannelCreate())
	can receive messages/pulses on it.  A channel is not needed to send,
	only to receive.  Yes, Process A will have to know the PID and CHID of
	process B, in order to send it a message.  Process A  only needs to call
	ChannelCreate() if it wants to receive messages itself.  FYI process A
	and Process B need to send messages one direction, not both (ie. A->B
	OR B->A, don't have A<->B), as you can get a deadlock if they send to
	each other.
	
	As for how to get the chid out of process B?  There are several methods:
	a shared memory region; printing the chid on the console, and passing it
	as a cmd-line arg to process A; resmgr_attach() and it's associated
	functions (note this is a more involved method, but great if you plan
	for your processes to register pathnames, and respond to all the
	"normal" POSIX operations).
	
	David
	
	> -----Original Message-----
	> From: Tim Gessner [mailto:community-noreply@qnx.com] 
	> Sent: September 9, 2008 5:36 PM
	> To: ostech-core_os
	> Subject: RE: ConnectAttach fails connecting to a daemon
	> 
	> Interesting, that is not how I read the documentation.  Since 
	> I can't know the channel of Proc B in Proc A - it is a FD 
	> created by the call to ChannelCreate in Proc B, there is no 
	> way to connect from Proc A if the ChId is created in Proc B.  
	> As I understood the documentation Proc B calls ChannelCreate 
	> and Proc A calls ChannelCreate.  The ChId passed into 
	> ConnectAttach in Proc A is the channel created by Proc A.
	> 
	> Am I still misunderstanding this?
	> 
	> Thanx
	> Tim
	> 
	> 
	> 
	> -----Original Message-----
	> From: Shiv Nagarajan [mailto:community-noreply@qnx.com]
	> Sent: Tuesday, September 09, 2008 2:25 PM
	> To: ostech-core_os
	> Subject: Re: ConnectAttach fails connecting to a daemon
	> 
	> So if process A is looking for proc B's pid, it should be 
	> connecting to proc B's channel, not creating a channel and 
	> connecting to it.
	> 
	> the nd, pid, chid being passed to the connectattach, refer to 
	> the owner of the channel.
	> 
	> so in your call 
	> 
	> 
	> int nCoID = ::ConnectAttach(ND_LOCAL_NODE,tPID,nChID,0 |
	>     _NTO_SIDE_CHANNEL,0);
	> 
	> should really be
	> 
	> In Proc A
	> 
	> ProcBpid = query for proc B pid
	> ProcBChid = proc B's channel
	> 
	> int nCoID = ::ConnectAttach(ND_LOCAL_NODE,ProcBPid,ProcBChid,0 |
	>     _NTO_SIDE_CHANNEL,0);
	> 
	> shiv
	> Tue Sep  9 17:23:57 EDT 2008
	> 
	>  --> According to Tim Gessner <--
	> 	Yes there is a server and a client and they are both daemons.
	> Proc A
	> 	gets an event and querys for Proc B's PID.  Proc A then calls
	> 	ChannelCreate and ConnectAttach to connect to Proc B.  
	> Proc A then sends
	> 	a message to Proc B.  The code snippet I just sent was 
	> from Proc A, the
	> 	process which is trying to connect.  The code to create 
	> the daemons is
	> 	identical other than the printf messages they display, "Server
	> 	starting... " "Client Starting..." and the class that 
	> is created CServer
	> 	CClient, etc.
	> 	
	> 	Does that make sense?  Essentially I have two daemons 
	> which both access
	> 	shared memory.  They communicate to each other (when 
	> necessary) through
	> 	messages.
	> 	
	> 	Thanx
	> 	Tim
	> 	
	> 	-----Original Message-----
	> 	From: Shiv Nagarajan [mailto:community-noreply@qnx.com] 
	> 	Sent: Tuesday, September 09, 2008 2:14 PM
	> 	To: ostech-core_os
	> 	Subject: Re: ConnectAttach fails connecting to a...