|RECV(3XNET)||X/Open Networking Services Library Functions||RECV(3XNET)|
recv - receive a message from a connected socket
cc [ flag ... ] file ... -lxnet [ library ... ] #include <sys/socket.h> ssize_t recv(int socket, void *buffer, size_t length, int flags);
The recv() function receives a message from a connection-mode or connectionless-mode socket. It is normally used with connected sockets because it does not permit the application to retrieve the source address of received data. The function takes the following arguments:
The recv() function returns the length of the message written to the buffer pointed to by the buffer argument. For message-based sockets such as SOCK_DGRAM and SOCK_SEQPACKET, the entire message must be read in a single operation. If a message is too long to fit in the supplied buffer, and MSG_PEEK is not set in the flags argument, the excess bytes are discarded. For stream-based sockets such as SOCK_STREAM, message boundaries are ignored. In this case, data is returned to the user as soon as it becomes available, and no data is discarded.
If the MSG_WAITALL flag is not set, data will be returned only up to the end of the first message.
If no messages are available at the socket and O_NONBLOCK is not set on the socket's file descriptor, recv() blocks until a message arrives. If no messages are available at the socket and O_NONBLOCK is set on the socket's file descriptor, recv() fails and sets errno to EAGAIN or EWOULDBLOCK.
The recv() function is identical to recvfrom(3XNET) with a zero address_len argument, and to read() if no flags are used.
Upon successful completion, recv() returns the length of the message in bytes. If no messages are available to be received and the peer has performed an orderly shutdown, recv() returns 0. Otherwise, -1 is returned and errno is set to indicate the error.
In addition to the errors documented below, an asynchronous error generated by the underlying socket protocol may be returned. For the full list of errors, please see the corresponding socket protocol manual page. For example, for a list of TCP errors, please see tcp(4P).
The recv() function will fail if:
The recv() function may fail if:
See attributes(7) for descriptions of the following attributes:
|ATTRIBUTE TYPE||ATTRIBUTE VALUE|
|September 10, 2018||OmniOS|