One of our digital signage applications was crashing when the control server was shutdown at the same time a command was sent with no apparent reason.
It would always crash inside the write function (see code below) and no error message were returned.
sent = write(fd, buf, n);
After a while, we found that in case the connection with the server is lost, and write tries to access the server, it will generate a SIGPIPE signal and in most systems, the application would just exit by default.
A simple way to handle this case was to ignore the pipe signal by adding the following line during initialization:
In case the server is down at the time the write function is called, the signal SIGPIPE would be ignored, write would return -1 and errno should return 32 (Broken pipe).
Alternatively, if needs be you could also handle the SIGPIPE signal in your own function.
Jean-Luc started CNX Software in 2010 as a part-time endeavor, before quitting his job as a software engineering manager, and starting to write daily news, and reviews full time later in 2011.