Current udp packets queue length

I have rather simple UDP server written on c. Sometimes i need to know current length of all udp packets(bytes) queued in socket. As i understand, getsockopt doesn't get such information.

Linux and FreeBSD solutions are both 开发者_如何学运维welcome, thanks!

ioctl(FIONREAD, ...) should be roughly what you are looking for,

http://www.daemon-systems.org/man/ioctl.2.html

From outside of the server (command line), you can do

netstat -uln

which will show you the length of all listening udp sockets.