restarting pigpiod result in "bind to port 8888 failed (Address already in use)"

[janvda]

I have defined a docker service (in balena) that runs the pigpiod daemon.
The problem is that when I try to restart that service, I am getting the following error:

04.10.19 08:35:11 (+0200)  pigpiod  2019-10-04 06:35:11 initInitialise: bind to port 8888 failed (Address already in use)
04.10.19 08:35:11 (+0200)  pigpiod  Can't initialise pigpio library

I strongly think that the operating system is not allowing immediately to rebind to the same port. So you should wait for TIME_WAIT period before a process again can bind to the same port.

[janvda]

For more details see also janvda/balena-node-red#1

[janvda]

This issue can be resolved by using the socket option SO_REUSEADDR (see https://stackoverflow.com/questions/21967311/linux-refuse-to-open-listening-port-from-localhost).

So it would be nice if you would consider setting this socket option.

[guymcswain]

I checked the code. SO_REUSEADDR is being used.

[guymcswain]

Please retest and provide more information if its still an issue. I tried to follow your links but found evidence the problem may have been resolved.

[maxnet]

You currently have:

            int opt;
            setsockopt(fdSock, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));

But think it should be instead:

            int opt = 1;
            setsockopt(fdSock, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));

[guymcswain]

@maxnet, You are correct! Thank you for reviewing the code and finding this oversight. Meanwhile, I need to bolster the testing around the network features.

[guymcswain]

@janvda , please retest with the patch for this issue in the 'develop' branch of this repo.

[dachshund-digital]

What this fix implemented? In version 78 or 79? I just encountered it on Pi OS buster Debian 10 (fully patched as of today). Happen to be running 78.

May 03 00:12:29 pi3modelb0 pigpiod[32482]: 2021-05-03 00:12:29 initInitialise: bind to port 8888 failed (Cannot assign requested address)
May 03 00:12:29 pi3modelb0 pigpiod[32482]: Can't initialise pigpio library
M

[guymcswain]

Yes both 78, 79. It was implemented in earlier version but don't recall which off the top of my head.