Hi,
On the Mac VM, when starting a second image with the same VM as an already running image, the second image opens the same TCP ports as the first image.
It is easy to see this. Start image A and do:
s := Socket newTCP. s listenOn: 7777.
as expected:
lsof -i | grep Squeak Squeak 1747 adrian 9u IPv4 0x9dafa68 0t0 TCP *:cbt (LISTEN)
Now, start image B (PID 1752).
lsof -i | grep Squeak Squeak 1747 adrian 9u IPv4 0x9dafa68 0t0 TCP *:cbt (LISTEN) Squeak 1752 adrian 9u IPv4 0x9dafa68 0t0 TCP *:cbt (LISTEN)
It will also listen on port 7777...
Is this a known limitation?
VM: 3.8.20beta1U Image: any (tested with Squeak 3.9 and 3.10)
Cheers, Adrian ___________________ http://www.adrian-lienhard.ch/
Ok, I assume you did
s := Socket newTCP. s listenOn: 7777.
in both images.
Yes Unix will allow that, this is not a squeak vm issue,
Check the socket options to see if any apply to your needs of preventing two apps from acquiring the same socket at the same time.
static socketOption socketOptions[]= { { "SO_DEBUG", SOL_SOCKET, SO_DEBUG }, { "SO_REUSEADDR", SOL_SOCKET, SO_REUSEADDR }, { "SO_DONTROUTE", SOL_SOCKET, SO_DONTROUTE }, { "SO_BROADCAST", SOL_SOCKET, SO_BROADCAST }, { "SO_SNDBUF", SOL_SOCKET, SO_SNDBUF }, { "SO_RCVBUF", SOL_SOCKET, SO_RCVBUF }, { "SO_KEEPALIVE", SOL_SOCKET, SO_KEEPALIVE }, { "SO_OOBINLINE", SOL_SOCKET, SO_OOBINLINE }, { "SO_LINGER", SOL_SOCKET, SO_LINGER }, { "IP_TTL", SOL_IP, IP_TTL }, { "IP_HDRINCL", SOL_IP, IP_HDRINCL }, { "IP_MULTICAST_IF", SOL_IP, IP_MULTICAST_IF }, { "IP_MULTICAST_TTL", SOL_IP, IP_MULTICAST_TTL }, { "IP_MULTICAST_LOOP", SOL_IP, IP_MULTICAST_LOOP }, #ifdef IP_ADD_MEMBERSHIP { "IP_ADD_MEMBERSHIP", SOL_IP, IP_ADD_MEMBERSHIP }, { "IP_DROP_MEMBERSHIP", SOL_IP, IP_DROP_MEMBERSHIP }, #endif { "TCP_MAXSEG", SOL_TCP, TCP_MAXSEG }, { "TCP_NODELAY", SOL_TCP, TCP_NODELAY }, #ifdef SO_REUSEPORT { "SO_REUSEPORT", SOL_SOCKET, SO_REUSEPORT }, #endif { (char *)0, 0, 0 } };
On 9-Jun-09, at 9:47 AM, Adrian Lienhard wrote:
Hi,
On the Mac VM, when starting a second image with the same VM as an already running image, the second image opens the same TCP ports as the first image.
It is easy to see this. Start image A and do:
s := Socket newTCP. s listenOn: 7777.
as expected:
lsof -i | grep Squeak Squeak 1747 adrian 9u IPv4 0x9dafa68 0t0 TCP *:cbt (LISTEN)
Now, start image B (PID 1752).
lsof -i | grep Squeak Squeak 1747 adrian 9u IPv4 0x9dafa68 0t0 TCP *:cbt (LISTEN) Squeak 1752 adrian 9u IPv4 0x9dafa68 0t0 TCP *:cbt (LISTEN)
It will also listen on port 7777...
Is this a known limitation?
VM: 3.8.20beta1U Image: any (tested with Squeak 3.9 and 3.10)
Cheers, Adrian ___________________ http://www.adrian-lienhard.ch/
-- = = = ======================================================================== John M. McIntosh johnmci@smalltalkconsulting.com Twitter: squeaker68882 Corporate Smalltalk Consulting Ltd. http://www.smalltalkconsulting.com = = = ========================================================================
Adrian Lienhard wrote:
On Jun 9, 2009, at 18:53 , John M McIntosh wrote:
Ok, I assume you did
s := Socket newTCP. s listenOn: 7777.
in both images.
No. Just in the first image.
I think it's more likely that you've got some code loaded that launches a listener automatically. Check Socket allInstances in the second image to see if there are any sockets.
Cheers, - Andreas
On Jun 9, 2009, at 23:47 , Andreas Raab wrote:
Adrian Lienhard wrote:
On Jun 9, 2009, at 18:53 , John M McIntosh wrote:
Ok, I assume you did
s := Socket newTCP. s listenOn: 7777.
in both images.
No. Just in the first image.
I think it's more likely that you've got some code loaded that launches a listener automatically. Check Socket allInstances in the second image to see if there are any sockets.
That's what I thought first too. But no, it happens also in vanilla images. There exist no socket instances in the second image.
Adrian
How are you starting the 2nd image, what is the procedure you do, double click an image, drag an image to the dock, use the cmd line, etc?
On 9-Jun-09, at 9:47 AM, Adrian Lienhard wrote:
Hi,
On the Mac VM, when starting a second image with the same VM as an already running image, the second image opens the same TCP ports as the first image.
-- = = = ======================================================================== John M. McIntosh johnmci@smalltalkconsulting.com Twitter: squeaker68882 Corporate Smalltalk Consulting Ltd. http://www.smalltalkconsulting.com = = = ========================================================================
Either by dragging the image on the icon of the already running VM in the dock, or by double clicking on the image.
Can somebody reproduce this or am I seeing ghosts?
Adrian
On Jun 10, 2009, at 08:48 , John M McIntosh wrote:
How are you starting the 2nd image, what is the procedure you do, double click an image, drag an image to the dock, use the cmd line, etc?
On 9-Jun-09, at 9:47 AM, Adrian Lienhard wrote:
Hi,
On the Mac VM, when starting a second image with the same VM as an already running image, the second image opens the same TCP ports as the first image.
-- = = = = = ====================================================================== John M. McIntosh johnmci@smalltalkconsulting.com Twitter: squeaker68882 Corporate Smalltalk Consulting Ltd. http:// www.smalltalkconsulting.com = = = = = ======================================================================
Adrian Lienhard wrote:
Either by dragging the image on the icon of the already running VM in the dock, or by double clicking on the image.
Can somebody reproduce this or am I seeing ghosts?
Well, there are strange things on the Mac in some ways. I don't recall but didn't John have to do special black magic to make this work at all (the Mac with its resistance to launching another instance of an app if one is running already)? Perhaps it's the side effect of doing a fork() that clones that socket handle implicitly?
Cheers, - Andreas
Oh yes I'm thinking it's the fork, I have to check where/how because the logic is *really old* and uses AppleScript to do the dirty work versus execve
Adrian gets bonus points for finding this since it's a really old mac vm *feature*...
On 10-Jun-09, at 1:01 AM, Andreas Raab wrote:
Adrian Lienhard wrote:
Either by dragging the image on the icon of the already running VM in the dock, or by double clicking on the image. Can somebody reproduce this or am I seeing ghosts?
Well, there are strange things on the Mac in some ways. I don't recall but didn't John have to do special black magic to make this work at all (the Mac with its resistance to launching another instance of an app if one is running already)? Perhaps it's the side effect of doing a fork() that clones that socket handle implicitly?
Cheers,
- Andreas
-- = = = ======================================================================== John M. McIntosh johnmci@smalltalkconsulting.com Twitter: squeaker68882 Corporate Smalltalk Consulting Ltd. http://www.smalltalkconsulting.com = = = ========================================================================
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