The class of error signaled while doing I/O on a socket.
comm
Instances of the condition class socket-io-error
are signaled when an error occured while performing I/O on a socket connection, which can be either a socket-stream or a async-io-state (which you can access by socket-error-connection). In most cases, that means that this connection cannot be used anymore, and you should close it and, if needed, try again.
LispWorks® User Guide and Reference Manual - 01 Dec 2021 19:30:26