NetBSD/common/lib/libprop/prop_send_ioctl.3

.\"	$NetBSD: prop_send_ioctl.3,v 1.5 2008/04/30 13:10:46 martin Exp $
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.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Jason R. Thorpe.
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.Dd January 21, 2008
.Dt PROP_SEND_IOCTL 3
.Os
.Sh NAME
.Nm prop_array_send_ioctl ,
.Nm prop_array_recv_ioctl ,
.Nm prop_dictionary_send_ioctl ,
.Nm prop_dictionary_recv_ioctl ,
.Nm prop_dictionary_sendrecv_ioctl
.Nd Send and receive propertly lists to and from the kernel using ioctl
.Sh SYNOPSIS
.In prop/proplib.h
.Ft int
.Fn prop_array_send_ioctl "prop_array_t array" "int fd" "unsigned long cmd"
.Ft int
.Fn prop_array_recv_ioctl "int fd" "unsigned long cmd" "prop_array_t *arrayp"
.Ft int
.Fn prop_dictionary_send_ioctl "prop_dictionary_t dict" "int fd" \
    "unsigned long cmd"
.Ft int
.Fn prop_dictionary_recv_ioctl "int fd" "unsigned long cmd" \
    "prop_dictionary_t *dictp"
.Fn prop_dictionary_sendrecv_ioctl "prop_dictionary_t dict" "int fd" \
    "unsigned long cmd" "prop_dictionary_t *dictp"
.Sh DESCRIPTION
The
.Nm prop_array_send_ioctl ,
.Nm prop_array_recv_ioctl ,
.Nm prop_dictionary_send_ioctl ,
.Nm prop_dictionary_recv_ioctl ,
and
.Nm prop_dictionary_sendrecv_ioctl
functions implement the user space side of a protocol for sending property
lists to and from the kernel using
.Xr ioctl 2 .
.Sh RETURN VALUES
If successful, functions return zero. Otherwise, an error number is returned to indicate the error.
.Sh ERRORS
.Fn prop_array_send_ioctl
and
.Fn prop_dictionary_send_ioctl
will fail if:
.Bl -tag -width Er
.It Bq Er ENOMEM
Cannot allocate memory
.It Bq Er ENOTSUP
Not supported
.El
.Pp
.Fn prop_array_recv_ioctl
and
.Fn prop_dictionary_recv_ioctl
will fail if:
.Bl -tag -width Er
.It Bq Er EIO
Input/output error
.It Bq Er ENOTSUP
Not supported
.El
.Pp
In addition to these,
.Xr ioctl 2
errors may be returned.
.Sh EXAMPLES
The following
.Pq simplified
example demonstrates using
.Fn prop_dictionary_send_ioctl
and
.Fn prop_dictionary_recv_ioctl
in an application:
.Bd -literal
void
foo_setprops(prop_dictionary_t dict)
{
    int fd;

    fd = open("/dev/foo", O_RDWR, 0640);
    if (fd == -1)
        return;

    (void) prop_dictionary_send_ioctl(dict, fd, FOOSETPROPS);

    (void) close(fd);
}

prop_dictionary_t
foo_getprops(void)
{
    prop_dictionary_t dict;
    int fd;

    fd = open("/dev/foo", O_RDONLY, 0640);
    if (fd == -1)
	return (NULL);

    if (prop_dictionary_recv_ioctl(fd, FOOGETPROPS, \*[Am]dict) != 0)
        return (NULL);

    (void) close(fd);

    return (dict);
}
.Ed
.Pp
The
.Nm prop_dictionary_sendrecv_ioctl
function combines the send and receive functionality, allowing for
ioctls that require two-way communication
.Pq for example to specify arguments for the ioctl operation .
.Sh SEE ALSO
.Xr prop_array 3 ,
.Xr prop_dictionary 3 ,
.Xr proplib 3 ,
.Xr prop_copyin_ioctl 9
.Sh HISTORY
The
.Nm proplib
property container object library first appeared in
.Nx 4.0 .