The uuencode module of Tcllib includes uudecode functionality.
For example, given a news post image.news, we can do:
package require uuencode
set data [uuencode::uudecode -file image.news]
foreach img $data {
set f [open [file tail [lindex $img 0]] w]
fconfigure $f -translation binary
puts -nonewline $f [lindex $img 2]
close $f
}Category Package, subset Tcllib see also uuencode