Millisecond clock

millisecond_clock.tcl

#!/usr/bin/env wish8.6

set intervalms 1
variable theclock

proc setclock {} {
    global intervalms theclock
    set micros [clock microseconds]
    set epoch  [expr $micros / 1000000]
    set micros [format "%06d" [expr $micros % 1000000]]
    # set theclock [clock format $epoch -format "%a %b %d %Y %H:%M:%S.$micros"]
    set theclock [clock format $epoch -format "%H:%M:%S.$micros"]
    after $intervalms [list setclock]
}

font create TtyFont -family "monospace" -size 160 -weight bold
pack [label .clock -font TtyFont -textvariable theclock]

grid .clock -row 1 -column 1
grid rowconfigure . 1 -weight 1
grid columnconfigure . 1 -weight 1

wm geometry . 1000x200+0+0

setclock