?RCS: $Id: d_kqueue.U 12100 2006-10-07 16:42:35Z cbiere $
?RCS:
?RCS: @COPYRIGHT@
?RCS:
?MAKE:d_kqueue: Myread Setvar cat rm +cc +ccflags +ldflags
?MAKE:	-pick add $@ %<
?S:d_kqueue:
?S:	This variable conditionally defines the HAS_KQUEUE symbol, which
?S:	indicates to the C program that kqueue() support is available.
?S:.
?C:HAS_KQUEUE:
?C:	This symbol is defined when kqueue() can be used.
?C:.
?H:#$d_kqueue HAS_KQUEUE
?H:.
?LINT: set d_kqueue
: can we use kqueue?
echo " "
echo "Checking whether kqueue() is available ..." >&4
val="$define"
$cat >try.c <<'EOC'
#include <sys/types.h>
#include <sys/event.h>
#include <sys/time.h>

int
main(void) {
  static struct kevent changes[1], events[1];
  static struct timespec ts;
  static unsigned long filters[] = { EVFILT_READ, EVFILT_WRITE,
    EVFILT_SIGNAL, EVFILT_PROC, EVFILT_VNODE };
  int kq = kqueue();
  int fd = 0;
  unsigned long flags;

  flags = EV_ADD | EV_ENABLE | EV_ONESHOT;
  flags &= ~(EV_CLEAR | EV_EOF | EV_ERROR | EV_DISABLE | EV_DELETE);
  EV_SET(&changes[0], fd, filters[0], flags, 0, 0, 0);
  kevent(kq, changes, 1, events, 1, &ts);

  return 0;
}
EOC
if $cc $ccflags $ldflags -o try try.c >/dev/null 2>&1; then
    $cat <<'EOM'
It looks like kqueue() is usable on your system, good.
EOM
else
	echo "Sorry, I will not be using kqueue()."
	val="$undef"
fi
$rm -f try try.c
set d_kqueue
eval $setvar