c - Can socket send fail cause a daemon program crash? -


i have 2 applications running on embedded linux board. 1 runs daemon , other acts interface it. communicate each other using unix sockets. handle abnormal termination of socket, tried terminating interface application [ctr+c]. result, daemon application crashes. since socket terminated, socket send failed error on daemon side, expected after daemon crashes. @ loss should debugging problem.

have set socket in daemon non-blocking mode ?

suppose code looks following:

while(1) { connfd = accept(listenfd, (struct sockaddr*)null, null); 

/* use fd */  func(connfd);

}

based on man page:

" on success, accept() return nonnegative integer descriptor accepted socket. on error, -1 returned, , errno set appropriately.

and

if no pending connections present on queue, , socket not marked nonblocking, accept() blocks caller until connection present. if socket marked nonblocking , no pending connections present on queue, accept() fails error eagain or ewouldblock. "

therefore, means if in non-blocking mode, should check return value of accept() instead of using directly because fd value -1.

the above 1 common possibility. if not case, can try use "sudo strace -p process_id" or carry out core file analysis understand why crashed.


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