|SENDMSG(3XNET)||X/Open Networking Services Library Functions||SENDMSG(3XNET)|
sendmsg - send a message on a socket using a message structure
cc [ flag ... ] file ... -lxnet [ library ... ] #include <sys/socket.h> ssize_t sendmsg(int socket, const struct msghdr *message, int flags);
The function takes the following arguments:
The sendmsg() function sends a message through a connection-mode or connectionless-mode socket. If the socket is connectionless-mode, the message will be sent to the address specified by msghdr. If the socket is connection-mode, the destination address in msghdr is ignored.
The msg_iov and msg_iovlen fields of message specify zero or more buffers containing the data to be sent. msg_iov points to an array of iovec structures; msg_iovlen must be set to the dimension of this array. In each iovec structure, the iov_base field specifies a storage area and the iov_len field gives its size in bytes. Some of these sizes can be zero. The data from each storage area indicated by msg_iov is sent in turn.
Successful completion of a call to sendmsg() does not guarantee delivery of the message. A return value of −1 indicates only locally-detected errors.
If space is not available at the sending socket to hold the message to be transmitted and the socket file descriptor does not have O_NONBLOCK set, sendmsg() function blocks until space is available. If space is not available at the sending socket to hold the message to be transmitted and the socket file descriptor does have O_NONBLOCK set, sendmsg() function will fail.
If the socket protocol supports broadcast and the specified address is a broadcast address for the socket protocol, sendmsg() will fail if the SO_BROADCAST option is not set for the socket.
The socket in use may require the process to have appropriate privileges to use the sendmsg() function.
Upon successful completion, sendmsg() function returns the number of bytes sent. 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 sendmsg() function will fail if:
If the address family of the socket is AF_UNIX, then sendmsg() will fail if:
The sendmsg() function may fail if:
If the address family of the socket is AF_UNIX, then sendmsg() may fail if:
See attributes(7) for descriptions of the following attributes:
|ATTRIBUTE TYPE||ATTRIBUTE VALUE|
poll(2) select(3C), getsockopt(3XNET), recv(3XNET), recvfrom(3XNET), recvmsg(3XNET), send(3XNET), sendto(3XNET), setsockopt(3XNET), shutdown(3XNET), socket(3XNET), tcp(4P), attributes(7), standards(7)
|September 10, 2018||OmniOS|