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MSENDL(3)		   libdill Library Functions		     MSENDL(3)

       msendl -	sends a	message

	      #include <libdill.h>

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

       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  partial send.	 If a problem, including timeout, occurs while
       sending the message error is returned to	the user and the socket	cannot
       be used for sending 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 following 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:

       o If last->iol_next is not NULL.

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

       o If there's a loop in the list.

       o 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  mil-
       liseconds.   Use	the now	function to get	your current point in time.  0
       means immediate timeout,	i.e., perform the operation if possible	or re-
       turn  without  blocking	if  not.  -1 means no deadline,	i.e., the call
       will block forever if the operation cannot be performed.

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

       o EBADF:	Invalid	handle.

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

       o ECANCELED: Current coroutine was canceled.

       o ECONNRESET: Broken connection.

       o EINVAL: Invalid argument.

       o EMSGSIZE: The message is too long.

       o ENOTSUP: The handle does not support this operation.

       o EPIPE:	Closed connection.

       o ETIMEDOUT: Deadline was reached.

       mrecv(3)	mrecvl(3) msend(3) now(3)

libdill								     MSENDL(3)


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