(filter_mail): Fix destruction of non-printable characters.

diff --git a/minc b/minc
index aab2b99..d2a85da 100755 (executable)
--- a/minc
+++ b/minc
@@ -584,8 +584,9 @@ sub filter_mail {
             $saved++;
             my $from = [@{$headers{'from'}}]->[-1];
             my $subject = [@{$headers{'subject'}}]->[-1];
-            $from =~ s/[[:cntrl:]]/?/g;
-            $subject =~ s/[[:cntrl:]]/?/g;
+            for ($from, $subject) {
+                tr/\x00-\x1f\x80-\xff/ /;
+            }
             print("\r");
             print(' ' x $COLUMNS);
             printf("\r\%-${nf}s \%${nm}d \%-${nF}s \%s\n",