sctp_sendmsg() Function

ssize_t sctp_sendmsg(s, *msg, len, *to, tolen, ppid, flags, stream_no, timetolive, context);
int s, const void *msg, size_t len, const struct sockaddr *to, socklen_t tolen, uint32_t ppid, uint32_t flags, uint16_t stream_no, uint32_t timetolive, uint32_t context;

The sctp_sendmsg() function enables advanced SCTP features while sending a message from an SCTP endpoint.

s

This value specifies the SCTP endpoint that is sending the message.

msg

This value contains the message sent by the sctp_sendmsg() function.

len

This value is the length of the message. This value is expressed in bytes.

to

This value is the destination address of the message.

tolen

This value is the length of the destination address.

ppid

This value is the application-specified payload protocol identifier.

stream_no

This value is the target stream for this message.

timetolive

This value is the time period after which the message expires if it has not been successfully sent to the peer. This value is expressed in milliseconds.

context

This value is returned if an error occurs during the sending of the message.

flags

This value is formed from applying the logical operation OR in bitwise fashion on zero or more of the following flag bits:

MSG_UNORDERED

When this flag is set, the sctp_sendmsg() function delivers the message unordered.

MSG_ADDR_OVER

When this flag is set, the sctp_sendmsg() function uses the address in the to parameter instead of the association's primary destination address. This flag is only used with one-to-many SCTP sockets model.

MSG_ABORT

When this flag is set, the specified association aborts by sending an ABORT signal to its peer. This flag is only used with one-to-many SCTP sockets model.

MSG_EOF

When this flag is set, the specified association enters graceful shutdown. This flag is only used with one-to-many SCTP sockets model.

MSG_PR_SCTP

When this flag is set, the message expires when its transmission has not successfully completed within the time period specified in the timetolive parameter.

The sctp_sendmsg() function returns the number of bytes it sent. The sctp_sendmsg() function returns -1 when an error occurs.

If the file descriptor passed in the s parameter is not valid, the sctp_sendmsg() function fails and sets the value of errno to EBADF. If the file descriptor passed in the s parameter does not describe a socket, the sctp_sendmsg() function fails and sets the value of errno to ENOTSOCK. If the flags parameter includes the value MSG_OOB, the sctp_sendmsg() function fails and sets the value of errno to EOPNOTSUPP. If the flags parameter includes the values MSG_ABORT or MSG_EOF for a one-to-one socket model, the sctp_sendmsg() function fails and sets the value of errno to EOPNOTSUPP. If there is no established association, the sctp_sendmsg() function fails and sets the value of errno to ENOTCONN. If the socket is shutting down, disallowing further writes, the sctp_sendmsg() function fails and sets the value of errno to EPIPE. If the socket is nonblocking and the transmit queue is full, the sctp_sendmsg() function fails and sets the value of errno to EAGAIN.

If the control message length is incorrect, the sctp_sendmsg() function fails and sets the value of errno to EINVAL. If the specified destination address does not belong to the association, the sctp_sendmsg() function fails and sets the value of errno to EINVAL. If the value of stream_no is outside the number of outbound streams that the association supports, the sctp_sendmsg() function fails and sets the value of errno to EINVAL. If the address family of the specified destination address is not AF_INET or AF_INET6, the sctp_sendmsg() function fails and sets the value of errno to EINVAL.