17.7. Socket Errors
A number of errno values occur only with sockets. Here is a list of socket-specific errors and a short description of each:
A requested address is already in use and cannot be reassigned.
An unavailable address was requested.
An unsupported address family was specified.
The connection was aborted by software.
The remote machine refused the connection attempt.
The connection was reset by the remote end. This usually indicates that the remote machine was restarted.
An attempt was made to send data over a socket without providing the destination address. This can occur only for datagram sockets.
The remote host is not on the network.
The remote host cannot be reached.
A connection is already established for the socket.
The data being sent through a socket is too large to be sent as a single, atomic message.
The network connection is down.
The network was reset, causing the connection to be dropped.
The specified network cannot be reached.
Not enough buffer space is available to handle the request.
An attempt to set an invalid option was made.
A connection must be established before the operation can succeed.
A socket-specific operation was attempted on a file descriptor that references a file other than a socket.
An unsupported protocol family was specified.
A request was made for an unsupported protocol.
An inappropriate protocol type was specified for the socket.
An attempt was made to create an unsupported socket type.
The connection timed out.