/usr/bin/tax2thesaurus is in libbiblio-thesaurus-perl 0.43-2.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 | #!/usr/bin/perl -s
eval 'exec /usr/bin/perl -s -S $0 ${1+"$@"}'
    if 0; # not running under some shell
use strict;
my @tab=(-1);
my @ant=("_top");
my $ind;
my $inda=0;
binmode(STDOUT,":utf8");
@ARGV = ("-") unless @ARGV;
for my $file (@ARGV){
 open(F,$file) or die("cant open $file\n");
 print "%enc utf8\n\n";
 while(<F>){ chomp;
   if(/%enc(oding)?\s+(latin1)/){next}
   if(/%enc(oding)?\s+(utf8)/i) {binmode(F,":utf8");next}
   my $termo;
   next unless /\w/;
   if(/^([ .-]*)(\S.*)/){
      $termo = $2;
      $ind = length($1);
##      print STDERR "Deb: $_($termo/$ind)\n";
      if ($ind <= $inda) { 
        while(@tab and $ind <= $tab[-1]){ pop(@tab); pop(@ant);}
      }
      push (@tab,$ind); 
      push (@ant,$termo);
      print "\n$termo\nBT  ",$ant[-2] ||"?","\n#lev ", @ant -1,"\n";
      $inda = $ind;
   }
 }
 close F;
}
__END__
=head1 NAME
tax2thesaurus - indented taxonomy to thesaurus
=head1 SYNOPSIS
 tax2thesaurus file.tax > file.the
=head1 DESCRIPTION
A top term C<_top> is added to the taxonomy.
=head2 example of the taxonomy format
 science
   physics
      dynamics
   math
      algebra
      trignometry
 literature
=head2 Correspondent output
 science
 BT  _top
 #lev 1
 
 physics
 BT  science
 #lev 2
 
 dynamics
 BT  physics
 #lev 3
 
 math
 BT  science
 #lev 2
 
 algebra
 BT  math
 #lev 3
 
 trignometry
 BT  math
 #lev 3
 
 literature
 BT  _top
 #lev 1
 
=head1 AUTHOR
J.Joao Almeida, jj@di.uminho.pt
=head1 SEE ALSO
perl(1).
=cut      
__END__
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 |