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MSENDL(3)		    libdill Library Functions		       MSENDL(3)

NAME
     msendl - sends a message

SYNOPSIS
	    #include <libdill.h>

	    int msendl(
		int s,
		struct iolist* first,
		struct iolist* last,
		int64_t deadline);

DESCRIPTION
     This function sends a message to a socket.  It is a blocking operation that
     unblocks only after entire message is sent.  There is no such thing as par-
     tial  send.  If a problem, including timeout, occurs while sending the mes-
     sage error is returned to the user and the socket cannot be used for  send-
     ing from that point on.

     This  function  accepts  a  linked  list of I/O buffers instead of a single
     buffer.  Argument first points to the first item in the list,  last  points
     to  the  last buffer in the list.	The list represents a single, fragmented
     message, not a list of multiple messages.	Structure iolist has the follow-
     ing members:

	    void *iol_base;	     /* Pointer to the buffer. */
	    size_t iol_len;	     /* Size of the buffer. */
	    struct iolist *iol_next; /* Next buffer in the list. */
	    int iol_rsvd;	     /* Reserved. Must be set to zero. */

     When receiving, iol_base equal to NULL means that iol_len bytes  should  be
     skipped.

     The function returns EINVAL error in the case the list is malformed:

     * If last->iol_next is not NULL.

     * If first and last don't belong to the same list.

     * If there's a loop in the list.

     * If iol_rsvd of any item is non-zero.

     The list (but not the buffers themselves) can be temporarily modified while
     the  function  is in progress.  However, once the function returns the list
     is guaranteed to be the same as before the call.

     s: The socket to send the message to.

     first: Pointer to the first item of a linked list of I/O buffers.

     last: Pointer to the last item of a linked list of I/O buffers.

     deadline: A point in time when the operation should time out, in  millisec-
     onds.  Use the now function to get your current point in time.  0 means im-
     mediate  timeout, i.e., perform the operation if possible or return without
     blocking if not.  -1 means no deadline, i.e., the call will  block  forever
     if the operation cannot be performed.

RETURN VALUE
     In  case of success the function returns 0.  In case of error it returns -1
     and sets errno to one of the values below.

ERRORS
     * EBADF: Invalid handle.

     * EBUSY: The handle is currently being used by a different coroutine.

     * ECANCELED: Current coroutine was canceled.

     * ECONNRESET: Broken connection.

     * EINVAL: Invalid argument.

     * EMSGSIZE: The message is too long.

     * ENOTSUP: The handle does not support this operation.

     * EPIPE: Closed connection.

     * ETIMEDOUT: Deadline was reached.

SEE ALSO
     mrecv(3) mrecvl(3) msend(3) now(3)

libdill 							       MSENDL(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=msendl&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>

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