Hi, I was thinking to tie the *STDOUT handle to mask the values to be printed in the stardard output. Though, I hit a deep recursion error, probably because I lose the original reference to *STDOUT and invokes my new handle when trying to print: 
package hyundai{
  
  sub TIEHANDLE{
    my $class = shift; 
    my $oldhandle = shift;
    return bless ({"handle" => $oldhandle}, $class); 
  }
  
  my $mask = sub{
    (my $text = shift()) =~ s/a/b/g; # replaces a with b
    return $text;
  };
  
  sub PRINT{
    my $self = shift;
    die("Not a ref") if !ref($self); 
    my $text = join('',@_);
    print STDERR ("STDOUT: ", \*STDOUT, "\n"); # prints GLOB(0x880a20)
+ 
    print STDERR ("STDERR: ", \*STDERR, "\n"); # prints GLOB(0x880a80)
    print STDERR ("handle: ", \$self->{"handle"}, "\n"); # prints GLOB
+(0x8806c0)
    
    $self->{"handle"}->print( &$mask($text) ); # infinite recursion !
  }
  
};


print("Hello world 1 aaaaaaa\n");
my $oldhandle = *STDOUT;
undef(*STDOUT);
tie *STDOUT, "hyundai", $oldhandle;
print("Hello world 2 aaaaaaa\n");

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I was following this (old) post related to the same issue, though it does not seem that a working solution was proposed. Any idea how to proceed ?

s.fox

In reply to Tie *STDOUT, recursion error by Superfox il Volpone

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