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FDIN(3)			   libdill Library Functions		       FDIN(3)

NAME
       fdin - waits on a file descriptor to become readable

SYNOPSIS
	      #include <libdill.h>

	      int fdin(
		  int fd,
		  int64_t deadline);

DESCRIPTION
       Waits on	a file descriptor (true	OS file	descriptor, not	libdill	socket
       handle) to either become	readable or get	into an	error  state.	Either
       case  leads  to	a successful return from the function.	To distinguish
       the two outcomes, follow	up with	a read operation on the	file  descrip-
       tor.

       fd: file	descriptor (OS-level one, not a	libdill	handle)

       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:	Not a file descriptor.

       o EBUSY:	Another	coroutine already blocked on fdin with this  file  de-
	 scriptor.

       o ECANCELED: Current coroutine was canceled.

       o ETIMEDOUT: Deadline was reached.

EXAMPLE
	      int result = fcntl(fd, F_SETFL, O_NONBLOCK);
	      assert(result == 0);
	      while(1) {
		  result = fdin(fd, -1);
		  assert(result	== 0);
		  char buf[1024];
		  ssize_t len =	recv(fd, buf, sizeof(buf), 0);
		  assert(len > 0);
		  process_input(buf, len);
	      }

SEE ALSO
       fdclean(3) fdout(3) now(3)

libdill								       FDIN(3)

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

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