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WS_RECV(3)		   libdill Library Functions		    WS_RECV(3)

NAME
       ws_recv - receives a WebSocket message

SYNOPSIS
	      #include <libdill.h>

	      ssize_t ws_recv(
		  int s,
		  int* flags,
		  void*	buf,
		  size_t len,
		  int64_t deadline);

DESCRIPTION
       WARNING:	 This  is experimental functionality and the API may change in
       the future.

       WebSocket is a message-based protocol defined in	RFC 6455.  It  can  be
       used  as	a bidirectional	communication channel for communication	with a
       web server.

       This function receives one WebSocket message.  It is very much the same
       as mrecv	except that it returns the type	of the message (either text or
       binary).

       s: The socket handle.

       flags: Out parameter.  Possible values are either WS_BINARYor WS_TEXT.

       buf: Buffer to receive the data to.

       len: Size of the	buffer,	in bytes.

       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.

       This function is	not available  if  libdill  is	compiled  with	--dis-
       able-sockets option.

RETURN VALUE
       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.

ERRORS
       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 ETIMEDOUT: Deadline was reached.

EXAMPLE
	      struct ipaddr addr;
	      ipaddr_remote(&addr, "www.example.org", 80, 0, -1);
	      int s = tcp_connect(&addr, -1);
	      s	= ws_attach_client(s, "/", "www.example.org", WS_TEXT, -1);
	      ws_send(s, WS_TEXT, "Hello, world!", 13, -1);
	      int flags;
	      char buf[256];
	      ssize_t sz = ws_recv(s, &flags, buf, sizeof(buf),	-1);
	      assert(flags & WS_TEXT);
	      s	= ws_detach(s, -1);
	      tcp_close(s, -1);

SEE ALSO
       mrecv(3)	mrecvl(3) msend(3) msendl(3) now(3) ws_attach_client(3)	ws_at-
       tach_client_mem(3) ws_attach_server(3)  ws_attach_server_mem(3)	ws_de-
       tach(3)	ws_done(3)  ws_recvl(3)	 ws_request_key(3)  ws_response_key(3)
       ws_send(3) ws_sendl(3) ws_status(3)

libdill								    WS_RECV(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLE | SEE ALSO

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