Final answer:
When a non-blocking connect() is successful and we're waiting in select(), the socket becomes writeable, indicating the connection is complete. We should check for errors with getsockopt() and SO_ERROR.
Step-by-step explanation:
If a non-blocking connect() operation is successful and we are waiting for it in select(), it means that the socket file descriptor will become 'writeable' to indicate that the connection has completed. The select() system call is commonly used to monitor multiple file descriptors to see if any of them are ready for reading, writing, or if an exception condition is pending.
When the non-blocking connect() completes, select() will indicate that the socket is ready for write operations, which typically means that the connection establishment is complete. It is then recommended to use getsockopt() with SO_ERROR to check if the connection was successful or if there were any errors.
If a non-blocking connect is successful and we are waiting for it in select(), it means that the connection request has been sent and the operating system is trying to establish a connection to the remote server. During this time, the select() function will block until the connection is either established or fails.
Once the connection is established, the select() function will return and the program can continue with the next steps.
However, if the connection is unsuccessful or fails before a certain timeout period, the select() function will also return, indicating the failure of the connection attempt.