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MRECVL(3)		   libdill Library Functions		     MRECVL(3)

       mrecvl -	receives a message

	      #include <libdill.h>

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

       This  function receives message from a socket.  It is a blocking	opera-
       tion that unblocks only after entire message is received.  There	is  no
       such thing as partial receive.  Either entire message is	received or no
       message at all.

       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.

       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.

       If  both	 first	and  last arguments are	set to NULL the	message	is re-
       ceived and silently dropped.  The function will still return  the  size
       of the message.

       In  case	 of success the	function returns size of the received message,
       in bytes.  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 data won't fit into the supplied	buffer.

       o ENOTSUP: The handle does not support this operation.

       o EPIPE:	Closed connection.

       o ETIMEDOUT: Deadline was reached.

       mrecv(3)	msend(3) msendl(3) now(3)

libdill								     MRECVL(3)


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