This function sends data to a connected peer. You can use this function only on connected sockets. To send data on an unconnected socket, use the sendmsg() or sendto() function. The send() function passes data along to its connected peer, which can receive the data by using the recv() or read() function. Normally the send() function blocks if there is no space for the incoming data in the buffer. It waits until the buffer space becomes available. If the socket is set to nonblocking and there is no space for the data, the send() function fails with the EWOULDBLOCK error. If the message is too large to be sent in one piece, and the socket type is SOCK_DGRAM, which requires that messages be sent in one piece, send() fails with the EMSGSIZE error. If the address specified is an INADDR_BROADCAST address, then the SO_BROADCAST socket option must have been set and the process must have SYSPRV or BYPASS privilege for the I/O operation to succeed. A success return from the send() does not guarantee that the data has been received by the peer. All errors (except EWOULDBLOCK) are detected locally. To determine when it is possible to send more data, use the select() function. Related Functions See also read(), recv(), recvmsg(), recvfrom(), getsockopt(), and socket().