Most demos are not working using Tcl/Tk 9.0.2 because of encoding problems.
They work fine using Tcl/Tk 8.6.17.

Example read_blocking_webpage.tcl:

`error reading "sock166e23c4e30": invalid or incomplete multibyte or wide character
    while executing
"read $ch 4096"
    (procedure "read_blocking" line 18)
    invoked from within
"read_blocking $host $port $path $protocol"
    invoked from within
"save_file "read_blocking_webpage.txt" [read_blocking $host $port $path $protocol]"
    (file "read_blocking_webpage.tcl" line 65)`