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NAME |SYNOPSIS |DESCRIPTION |RETURN VALUE |SEE ALSO |COLOPHON | |
SCTP_SENDMSG(3) Linux Programmer's ManualSCTP_SENDMSG(3)sctp_sendmsg - Send a message from a SCTP socket.
#include <sys/types.h>#include <sys/socket.h>#include <netinet/sctp.h>int sctp_sendmsg(intsd, const void *msg, size_tlen,struct sockaddr *to, socklen_ttolen,uint32_tppid, uint32_tflags,uint16_tstream_no, uint32_ttimetolive,uint32_tcontext);
sctp_sendmsgis a wrapper library function that can be used to send a message from a socket while using the advanced features of SCTP.sd is the socket descriptor from which the message pointed to bymsg of lengthlen is sent.to is the destination address of the message andtolen is the length of the destination address.stream_no identifies the stream number that the application wishes to send this message to.flags parameter is composed of a bitwise OR of the following values.SCTP_UNORDERED This flags requests the un-ordered delivery of the message.SCTP_ADDR_OVER This flag, in the one-to-many style, requests the SCTP stack to override the primary destination address with address specified into.SCTP_ABORT Setting this flag causes the specified association to abort by sending an ABORT message to the peer(one-to-many style only). The ABORT chunk will contain an error cause 'User Initiated Abort' with cause code 12. The cause specific information of this error cause is provided inmsg.SCTP_EOF Setting this flag invokes the SCTP graceful shutdown procedure on the specific association(one-to-many style only).SCTP_SENDALL This flag, if set, will cause a one-to-many style socket to send the message to all associations that are currently established on this socket. For the one-to-one style socket, this flag has no effect.SCTP_SACK_IMMEDIATELY This flag allows the application to set the I bit of the last DATA chunk when sending each user message to make sure the corresponding SACK can be sent by peer without delay.SCTP_PR_SCTP_{TTL|RTX|PRIO} One of these 3 pr_policies can be used through this flag with its pr_value set in timetolive parameter for this message. Note thatsctp_sendv(3) with infotype SCTP_SENDV_PRINFO also works for PR-SCTP.timetolive specifies the time duration in milliseconds. The sending side will expire the message if the message has not been sent to the peer within this time period. A value of 0 indicates that no timeout should occur on this message. It also works as the pr_value if flags parameter is set to pr_policy.ppid is an opaque unsigned value that is passed to the remote end along with the message.context is a 32 bit opaque value that is passed back to the upper layer along with the undelivered message if an error occurs on the send of the message.On success,sctp_sendmsgreturns the number of bytes sent or -1 if an error occurred.
sctp(7)sctp_bindx(3),sctp_connectx(3),sctp_sendv(3),sctp_send(3),sctp_recvmsg(3),sctp_recvv(3),sctp_peeloff(3),sctp_getpaddrs(3),sctp_getladdrs(3),sctp_opt_info(3),
This page is part of thelksctp-tools (Linux kernel SCTP tools) project. Information about the project can be found at [unknown -- if you know, please contact man-pages@man7.org] If you have a bug report for this manual page, send it to sctp@vger.kernel.org. This page was obtained from the project's upstream Git repository ⟨https://github.com/sctp/lksctp-tools.git⟩ on 2025-08-11. (At that time, the date of the most recent commit that was found in the repository was 2024-09-26.) If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up-to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which isnot part of the original manual page), send a mail to man-pages@man7.orgLinux 2.6 2004-10-25SCTP_SENDMSG(3)Pages that refer to this page:sctp_bindx(3), sctp_connectx(3), sctp_getladdrs(3), sctp_getpaddrs(3), sctp_opt_info(3), sctp_peeloff(3), sctp_recvmsg(3), sctp_recvv(3), sctp_send(3), sctp(7)
HTML rendering created 2025-09-06 byMichael Kerrisk, author ofThe Linux Programming Interface. For details of in-depthLinux/UNIX system programming training courses that I teach, lookhere. Hosting byjambit GmbH. | |