sctp_recvv

SCTP_RECVV(3)                        Linux                       SCTP_RECVV(3)

NAME
       sctp_recvv  -  Receive  a message from a SCTP socket with an extensible
       way.

SYNOPSIS
       #include <sys/types.h>
       #include <sys/socket.h>
       #include <netinet/sctp.h>

       int sctp_recvv(int sd, const struct iovec * iov, int iovlen,
                      struct sockaddr * from, socklen_t * fromlen, void * info,
                      socklen_t * infolen, unsigned int * infotype, int * flags);

DESCRIPTION
       sctp_recvv provides an extensible way for the SCTP  stack  to  pass  up
       different  SCTP attributes associated with a received message to an ap-
       plication.  There are two types of attributes that can be  returned  by
       this  call:  the attribute of the received message and the attribute of
       the next message  in  the  receive  buffer.   The  caller  enables  the
       SCTP_RECVRCVINFO  and SCTP_RECVNXTINFO socket options, respectively, to
       receive these attributes.  Attributes of the received message  are  re-
       turned  in  struct sctp_rcvinfo, and attributes of the next message are
       returned in struct sctp_nxtinfo.  If both options are enabled, both at-
       tributes are returned using the following structure.

          struct sctp_recvv_rn {
            struct sctp_rcvinfo recvv_rcvinfo;
            struct sctp_nxtinfo recvv_nxtinfo;
          };

       sd  is  the socket descriptor.  iov is the scatter buffer, and only one
       user message is returned in this buffer.  iovlen is the number of  ele-
       ments  in  iov.   from  is  a pointer to a buffer to be filled with the
       sender of the received message's address.  fromlen is an in/out parame-
       ter  describing  the  from  length.  info is a pointer to the buffer to
       hold the attributes of the received message, the structure type of info
       is determined by the info_type parameter.  infolen is an in/out parame-
       ter describing the size of the info buffer.  On return, infotype is set
       to  the  type of the info buffer, and the current defined values are as
       follows:

       SCTP_RECVV_NOINFO
              If neither SCTP_RECVRCVINFO nor SCTP_RECVNXTINFO options are en-
              abled,  no attribute will be returned.  If only the SCTP_RECVNX-
              TINFO option is enabled but there is no next message in the buf-
              fer,  no attribute will be returned.  In these cases, *info_type
              will be set to SCTP_RECVV_NOINFO.

       SCTP_RECVV_RCVINFO
              The type of info is struct sctp_rcvinfo, and the  attribute  re-
              lates to the received message.

       SCTP_RECVV_NXTINFO
              The  type  of info is struct sctp_nxtinfo, and the attribute re-
              lates to the next message in the receive buffer.   This  is  the
              case  when only the SCTP_RECVNXTINFO option is enabled and there
              is a next message in the buffer.

       SCTP_RECVV_RN
              The type of info is  struct  sctp_recvv_rn.   The  recvv_rcvinfo
              field  is  the  attribute  of  the  received  message,  and  the
              recvv_nxtinfo field is the attribute of the next message in  the
              buffer.   This  is  the  case  when  both  SCTP_RECVRCVINFO  and
              SCTP_RECVNXTINFO options are enabled and there is a next message
              in the receive buffer.

       flags  is  pointer  to  an  integer to be filled with any message flags
       (e.g., MSG_NOTIFICATION).

RETURN VALUE
       On success, sctp_recvv returns the number of bytes received or -1 if an
       error occurred.

SEE ALSO
       sctp(7)      sctp_bindx(3),      sctp_connectx(3),     sctp_sendmsg(3),
       sctp_sendv(3),   sctp_send(3),   sctp_peeloff(3),    sctp_getpaddrs(3),
       sctp_getladdrs(3), sctp_opt_info(3)

Linux 4.16                        2018-04-29                     SCTP_RECVV(3)