Richard Suchenwirth 2004-05-12 - "Quoted-printable" is a way of encoding 8-bit characters by using only 7-bit ASCII characters, by replacing them with =XX, XX being two hex digits. This is used for instance in MIME mail attachments. Decoding this type of data goes in a one-liner with subst:
proc quoted-printable s {subst -nocom -novar [string map {== = = \\u00} $s]}The other way it seems to need explicit iteration:
proc to-quoted-printable s {
set res ""
foreach char [split $s ""] {
scan $char %c i
if {$i>255} {error "character $i does not fit in 8 bits"}
append res [expr {$i<128? $char: [format =%02X $i]}]
}
set res
}# Test and demo:
% to-quoted-printable "Schöne Grüße" Sch=F6ne Gr=FC=DFe