c - domain socket "sendto" encounter "errno 111, connection refused" -

I am using a domain socket to get value from another process, such as obtaining a value from B For, this works well for months. But recently, during the "sendto" message, "failed with error 111" has failed for the B, sometimes the connection refused.

I checked the B domain socket bind file, it exists, I also do some tests in another machine, it also works well. So, before anyone is facing this problem? Does anyone have some wrong signals in this scenario? Thanks a lot.

When I have seen this error with Unix domain sockets, it is usually because process B There is no mismatch in running, or connection paths. (If B dies, does it restart automatically? Is it possible that B is going to die, but failure is still happening when there is no restart?). Another possibility: Is it possible that many copies of A are running at the same time? If you have not yet been in a row of the unbearable connection, then you can get anonfruid error.

Code>

Or, if the process is already running,

  strace -o B.log -P & LT; Process-id-of-B>  

In addition,

  netstat -na  

will give the status of all Unix domain sockets present in the system.