.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
.\"
.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
.\"
examines a set of file descriptors
to see if some of them are ready for I/O
or if certain events have occurred on them.
examines a set of file descriptors
to see if some of them are ready for I/O
or if certain events have occurred on them.
returns the number of descriptors that are ready for I/O,
or -1 if an error occurred.
If the time limit expires,
returns the number of descriptors that are ready for I/O,
or -1 if an error occurred.
If the time limit expires,