LDI_POLL(9F) Kernel Functions for Drivers LDI_POLL(9F)

NAME

ldi_poll - Poll a device

SYNOPSIS

#include <sys/sunldi.h>


int ldi_poll(ldi_handle_t lh, short events, int anyyet, short *reventsp,
struct pollhead **phpp);

PARAMETERS

lh
Layered handle.


events
Potential events. Valid events are:

POLLIN
Data other than high priority data may be read
without blocking.


POLLOUT
Normal data may be written without blocking.


POLLPRI
High priority data may be received without
blocking.


POLLHUP
Device hangup has occurred.


POLLERR
An error has occurred on the device.


POLLRDNORM
Normal data (priority band = 0) may be read
without blocking.


POLLRDBAND
Data from a non-zero priority band may be read
without blocking.


POLLWRNORM
Data other than high priority data may be read
without blocking.


POLLWRBAND
Priority data (priority band > 0) may be
written.


anyyet
A flag that is non-zero if any other file descriptors
in the pollfd array have events pending. The poll(2) system
call takes a pointer to an array of pollfd
structures as one of its arguments. See poll(2) for more
details.


reventsp
Pointer to a bitmask of the returned events satisfied.


phpp
Pointer to a pointer to a pollhead structure.

DESCRIPTION

The ldi_poll() function passes a poll request to the device entry point
for the device specified by the layered handle. This operation is
supported for block, character, and streams devices.

RETURN VALUES

The ldi_poll() function returns 0 upon success. If a failure occurs
before the request is passed on to the device, possible return values
are:

EINVAL
Invalid input parameters.


ENOTSUP
Operation is not supported for this device.

CONTEXT

These functions may be called from user or kernel context.


June 3, 2003 LDI_POLL(9F)