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  { my $eof = eof(FH);
    ### $eof
  }
  my $entry = readline(FH);
  ### $entry
  $entry = readline(FH);
  ### $entry
  my @entries = readline(FH);
  ### @entries
  exit 0;
}
 
{
  tie *FH, 'File::Locate::Iterator::TieHandle',
    use_mmap => 0,
      database_file => 't/samp.locatedb',
        ;
  my $fileno = fileno(FH);
  my $pos = tell(FH);
  ### $fileno
  ### $pos
  my $line = <FH>;
  ### $line
  $line = <FH>;
  ### $line

  my $buf; # = 'x';
  my $ret = read(FH,$buf,2,3);
  ### $ret
  ### $buf

  my $c = getc(FH);
  ### $c
  $c = getc(FH);
  ### $c
  # $line = <FH>;
  # ### $line

  $pos = tell(FH);
  ### $pos
  my @entries = readline(FH);
  ### @entries
  exit 0;
}
{
  open FH, '</etc/passwd' or die;
  my $buf;
  my $ret = read(FH,$buf,8,3);
  ### $ret
  ### $buf

  print <FH>;
  exit 0;
}



1;
__END__

=for stopwords filename filenames filesystem slocate filehandle arrayref mmap mmaps seekable PerlIO mmapped XSUB coroutining fd Findutils Ryde wildcard charset wordsize wildcards

=head1 NAME

File::Locate::Iterator::TieHandle -- file handle tied to read "locate" database

=head1 SYNOPSIS

 use File::Locate::Iterator::TieHandle;
 tie *FH, 'File::Locate::Iterator::TieHandle';
 while (defined (my $line = <FH>)) {
   chomp $line;
   print "entry is \"$line\"\n";
 }

=head1 DESCRIPTION

C<File::Locate::Iterator::TieHandle> ties a file handle to read entries from
a "locate" database file.  Each C<readline()> returns an entry from the
database.  C<read()> and C<getc()> can also be used.  Writing is not
implemented (as yet).

Each entry has the input record separator C<$/> appended (see L<perlvar>) as
if it was a line from an ordinary file.  This can be stripped with C<chomp>
etc in the usual way (see L<perlfunc/chomp>.

=head2 C<seek> and C<tell>

C<tell> gives the current database position in bytes.  Normally the only use
for this is to pass to C<seek> to go back to that position again.

C<seek> works as long as the underlying locate database file or handle is
seekable, as per C<rewind()> of L<File::Locate::Iterator/Operations>.

Seeking back to the start of the file is simply an iterator C<rewind>.
Seeking back by a small amount is slow in the current implementation because
the database must be re-read from the start to the target position, but at
least it works.

=head1 SEE ALSO

L<File::Locate::Iterator>, L<perltie>

=head1 HOME PAGE

http://user42.tuxfamily.org/file-locate-iterator/index.html

=head1 COPYRIGHT

Copyright 2011 Kevin Ryde

File-Locate-Iterator is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option) any
later version.

File-Locate-Iterator is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
Public License for more details.