c:\@Work\Perl\monks>perl -wMstrict -le
"my $consonants = qr{ [^aeiouAEIOU]+ }xms;
 ;;
 my $s = qq{four score\nand seven\nyears ago\nour fathers\n};
 print qq{>$s<};
 ;;
 my $offset = 0;
 my $pos;
 while (0 <= ($pos = index $s, qq{\n}, $offset)) {
   substr($s, $offset, $pos) =~ s{ ($consonants) }{\U$1}xmsg;
   $offset = ++$pos;
   }
 print qq{>$s<};
"
>four score
and seven
years ago
our fathers
<
>FouR SCoRe
aND SeVeN
YeaRS aGo
ouR FaTHeRS
<

##</code><code>##

c:\@Work\Perl\monks>perl -wMstrict -le
"my $consonants = qr{ [^aeiouAEIOU]+ }xms;
 ;;
 my $s = qq{four score\nand seven\nyears ago\nour fathers\n};
 print qq{>$s<};
 ;;
 my $offset = 0;
 my $pos;
 while (0 <= ($pos = index $s, qq{\n}, $offset)) {
   printf qq{==%s== \n}, substr($s, $offset, $pos-$offset);
   substr($s, $offset, $pos-$offset) =~ s{ ($consonants) }{\U$1}xmsg;
   $offset = ++$pos;
   }
 print qq{>$s<};
"
>four score
and seven
years ago
our fathers
<
==four score==
==and seven==
==years ago==
==our fathers==
>FouR SCoRe
aND SeVeN
YeaRS aGo
ouR FaTHeRS
<

##</code><code>##

c:\@Work\Perl\monks>perl -wMstrict -le
"my $consonants = qr{ [^aeiouAEIOU]+ }xms;
 ;;
 my $s = qq{four score\nand seven\nyears ago\nour fathers\n};
 print qq{>$s<};
 ;;
 my $offset = 0;
 my $pos;
 while (0 <= ($pos = index $s, qq{\n}, $offset)) {
   process(substr $s, $offset, $pos-$offset);
   $offset = ++$pos;
   }
 print qq{>$s<};
 ;;
 sub process {
   printf qq{==%s== \n}, $_[0];
   $_[0] =~ s{ ($consonants) }{\U$1}xmsg;
   }
"
>four score
and seven
years ago
our fathers
<
==four score==
==and seven==
==years ago==
==our fathers==
>FouR SCoRe
aND SeVeN
YeaRS aGo
ouR FaTHeRS
<