UDP for Tcl

The Tcl core has supported TCP sockets via socket since version 7 or so, but UDP must be supplied by an extension.

See Also

UDP in the Tcl core

UDP Protocols

Trivial FTP

Tcl UDP Extensions

The following extensions provide UDP support:

TclUDP
The normal package for standard UDP client/server programs. It is quite simple to use.
Tcl-dp
An extensive TCP/IP package which also supports UDP
Scotty
An SNMP package with its own UDP implementation
pktsrc
Access to raw IP Datagram and thus to UDP
ceptcl
Communications EndPoints for Tcl
Packet
A few Tcl routines for manipulating network packets
UDP extension
a small and clean critcl-based extension written in 2011 by CMcC
Duft
Datagrams and Udp For Tcl

UDP enabled packages

PT: The dns package in tcllib is capable of using udp if available. So are the time and ntp packages.