in reply to bitmask to vector problem

Does this help? 

my $v = 'DA39A3EE5E6B4B0D3255BFEF95601890AFD80709';
my $m = 'FFFF804020100804020100804020100804000102';
my $vb = unpack 'B*', pack 'H40', $v;
my $mb = unpack 'B*', pack 'H40', $m;
my $rb = $vb & $mb;
print unpack 'H*', pack 'B*', $rb;

da39804000000804020100800020100004000100

[download]
Or as a "one-liner": 
perl -le"print unpack'H*', pack'B*', 
unpack('B*',pack'H*','DA39A3EE5E6B4B0D3255BFEF95601890AFD80709') & 
unpack('B*',pack'H*','FFFF804020100804020100804020100804000102')"

da39804000000804020100800020100004000100

[download]
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Love the truth but pardon error.

In Section Seekers of Perl Wisdom