Weather update client in Tcl

#
# Weather update client

  1. Connects SUB socket to tcp:#localhost:5556
  2. Collects weather updates and finds avg temp in zipcode

#

package require zmq

# Socket to talk to server
zmq context context
zmq socket subscriber context SUB
subscriber connect "tcp://localhost:5556"

# Subscribe to zipcode, default is NYC, 10001
if {[llength $argv]} {
set filter [lindex $argv 0]
} else {
set filter "10001"
}

subscriber setsockopt SUBSCRIBE $filter

# Process 100 updates
set total_temp 0
for {set update_nbr 0} {$update_nbr < 100} {incr update_nbr} {
zmq message msg
subscriber recv_msg msg
lassign [msg data] zipcode temperature relhumidity
puts [msg data]
msg close
incr total_temp $temperature
}

puts "Averate temperatur for zipcode $filter was [expr {$total_temp/$update_nbr}]F"

subscriber close
context term