A little different way does it with one s///, but some other helpers. 
my $str = 't?e\\\\xt\\\\* with escapes\\*';
my %swap;
@swap{'?','*'} = ('#','?');

$str=~s/((?:\\)(.)|\?|\*)/$swap{$1}||$2/ge;

print ">>$str<<\n";

[download]
Ikegami points out that the (?:\\) can just be \\.
Caution: Contents may have been coded under pressure.

In reply to Re: Replace only unescaped metachars by Roy Johnson
in thread Replace only unescaped metachars by Anonymous Monk

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