[perl #125828] [BUG] Unexpected behavior with `getc` in raw mode

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# New Ticket Created by  kuerbis 
# Please include the string:  [perl #125828]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=125828 >


Hi, when I run this script

     #!/usr/bin/env perl6
     use v6;
     use Term::termios;

     my $saved_termios := Term::termios.new(fd => 1).getattr;
     my $termios := Term::termios.new(fd => 1).getattr;
     $termios.makeraw;
     $termios.setattr(:DRAIN);

     loop {
        my $c = $*IN.getc;
        print "got: " ~ $c.ord ~ "\r\n";
        last if $c eq 'q';
     }

     $saved_termios.setattr(:DRAIN);

  and press the keys <kbd>up-arrow</kbd>, <kbd>down-arrow</kbd>, 
<kbd>right-arrow</kbd>, <kbd>left-arrow</kbd> and <kbd>q</kbd> I get 
this output:

     #after arrow-up:
     got: 27
     got: 91

     #after arrow-down:
     got: 65
     got: 27
     got: 91

     #after arrow-right:
     got: 66
     got: 27
     got: 91

     #after arrow-left:
     got: 67
     got: 27
     got: 91

     #after q:
     got: 68

     #after another q:
     got: 113

But I would have expected this output:

     #after arrow-up:
     got: 27
     got: 91
     got: 65

     #after arrow-down:
     got: 27
     got: 91
     got: 66

     #after arrow-right:
     got: 27
     got: 91
     got: 67

     #after arrow-left:
     got: 27
     got: 91
     got: 68

     #after q:
     got: 113