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CHRECV(3)		   libdill Library Functions		     CHRECV(3)

NAME
       chrecv -	receives a message from	a channel

SYNOPSIS
	      #include <libdill.h>

	      int chrecv(
		  int ch,
		  void*	val,
		  size_t len,
		  int64_t deadline);

DESCRIPTION
       Receives	a message from a channel.

       The  size of the	message	requested from the channel must	match the size
       of the message sent to the channel.  Otherwise, both  peers  fail  with
       EMSGSIZE	error.

       If  there's no one sending a message at the moment, the function	blocks
       until someone shows up or until the deadline expires.

       ch: The channel.

       val: The	buffer to receive the message 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.

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
       o EBADF:	Invalid	handle.

       o ECANCELED: Current coroutine was canceled.

       o EINVAL: Invalid argument.

       o EMSGSIZE: The peer sent a message of different	size.

       o ENOTSUP: The handle does not support this operation.

       o EPIPE:	Channel	has been closed	with chdone.

       o ETIMEDOUT: Deadline was reached.

EXAMPLE
	      int val;
	      int rc = chrecv(ch, &val,	sizeof(val), now() + 1000);
	      if(rc != 0) {
		  perror("Cannot receive message");
		  exit(1);
	      }
	      printf("Value %d received.\n", val);

SEE ALSO
       chdone(3) chmake(3) chmake_mem(3) choose(3) chsend(3) now(3)

libdill								     CHRECV(3)

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

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