NAME

prop_object_send_ioctl, prop_object_recv_ioctl, prop_object_sendrecv_ioctl — Send and receive property lists to and from the kernel using ioctl

SYNOPSIS

#include <prop/proplib.h>

int
prop_object_send_ioctl(prop_object_t obj, int fd, unsigned long cmd);

int
prop_object_recv_ioctl(int fd, unsigned long cmd, prop_object_t *objp);

int
prop_object_sendrecv_ioctl(prop_object_t dict, int fd, unsigned long cmd, prop_object_t *objp);

DESCRIPTION

The prop_object_send_ioctl(), prop_object_recv_ioctl(), and prop_object_sendrecv_ioctl() functions implement the user space side of a protocol for sending property lists to and from the kernel using ioctl(2).

The functions prop_array_send_ioctl(), prop_array_recv_ioctl(), prop_dictionary_send_ioctl(), prop_dictionary_recv_ioctl(), and prop_dictionary_sendrecv_ioctl() are provided as wrappers around the corresponding generic object functions for backwards compatibility.

RETURN VALUES

If successful, functions return zero. Otherwise, an error number is returned to indicate the error.

EXAMPLES

The following (simplified) example demonstrates using prop_object_send_ioctl() and prop_object_recv_ioctl() in an application:

void
foo_setprops(prop_dictionary_t dict)
{
    int fd;

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

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

    (void) close(fd);
}

prop_dictionary_t
foo_getprops(void)
{
    prop_object_t obj;
    int fd;

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

    if (prop_object_recv_ioctl(fd, FOOGETPROPS, &obj) != 0)
        return (NULL);

    (void) close(fd);

    return (obj);
}

The prop_object_sendrecv_ioctl() function combines the send and receive functionality, allowing for ioctls that require two-way communication (for example to specify arguments for the ioctl operation).

ERRORS

prop_object_send_ioctl() will fail if:

[ENOMEM]

Cannot allocate memory

prop_object_recv_ioctl() will fail if:

[EIO]

Input/output error

In addition to these, ioctl(2) errors may be returned.

SEE ALSO

prop_array(3), prop_dictionary(3), proplib(3), prop_copyin_ioctl(9)

HISTORY

The proplib(3) property container object library first appeared in NetBSD 4.0.