User-mode and kernel driver communication

is there a way that an application running at user-mode can communicate with another application at the kernel mode.

For example, I would like to collect some infomation from the network driver and feed it some sniffer app running at user lever.

How do I proceed . Please advise.

One way to create a char/block device driver. Your application can then use regular IO calls like open, read, write, ioctl, & etc.

http://www.networkcomputing.com/unixworld/tutorial/010/010.txt.html

There's also sysfs, procfs, debugfs, netlink... char/block device is probably what you want though.