<h2>Editing File: /lib64/perl5/NDBM_File.pm</h2><form method='post'><textarea name='content' class='file-edit'>package NDBM_File;

use strict;
use warnings;

require Tie::Hash;
require XSLoader;

our @ISA = qw(Tie::Hash);
our $VERSION = &quot;1.14&quot;;

XSLoader::load();

1;

__END__

=head1 NAME

NDBM_File - Tied access to ndbm files

=head1 SYNOPSIS

  use Fcntl;   # For O_RDWR, O_CREAT, etc.
  use NDBM_File;

  tie(%h, 'NDBM_File', 'filename', O_RDWR|O_CREAT, 0666)
    or die &quot;Couldn't tie NDBM file 'filename': $!; aborting&quot;;

  # Now read and change the hash
  $h{newkey} = newvalue;
  print $h{oldkey};
  ...

  untie %h;

=head1 DESCRIPTION

C&lt;NDBM_File&gt; establishes a connection between a Perl hash variable and
a file in NDBM_File format;.  You can manipulate the data in the file
just as if it were in a Perl hash, but when your program exits, the
data will remain in the file, to be used the next time your program
runs.

Use C&lt;NDBM_File&gt; with the Perl built-in C&lt;tie&gt; function to establish
the connection between the variable and the file.  The arguments to
C&lt;tie&gt; should be:

=over 4

=item 1.

The hash variable you want to tie.

=item 2.

The string C&lt;&quot;NDBM_File&quot;&gt;.  (Ths tells Perl to use the C&lt;NDBM_File&gt;
package to perform the functions of the hash.)

=item 3.

The name of the file you want to tie to the hash.

=item 4.

Flags.  Use one of:

=over 2

=item C&lt;O_RDONLY&gt;

Read-only access to the data in the file.

=item C&lt;O_WRONLY&gt;

Write-only access to the data in the file.

=item C&lt;O_RDWR&gt;

Both read and write access.

=back

If you want to create the file if it does not exist, add C&lt;O_CREAT&gt; to
any of these, as in the example.  If you omit C&lt;O_CREAT&gt; and the file
does not already exist, the C&lt;tie&gt; call will fail.

=item 5.

The default permissions to use if a new file is created.  The actual
permissions will be modified by the user's umask, so you should
probably use 0666 here. (See L&lt;perlfunc/umask&gt;.)

=back

=head1 DIAGNOSTICS

On failure, the C&lt;tie&gt; call returns an undefined value and probably
sets C&lt;$!&gt; to contain the reason the file could not be tied.

=head2 C&lt;ndbm store returned -1, errno 22, key &quot;...&quot; at ...&gt;

This warning is emitted when you try to store a key or a value that
is too long.  It means that the change was not recorded in the
database.  See BUGS AND WARNINGS below.

=head1 BUGS AND WARNINGS

There are a number of limits on the size of the data that you can
store in the NDBM file.  The most important is that the length of a
key, plus the length of its associated value, may not exceed 1008
bytes.

See L&lt;perlfunc/tie&gt;, L&lt;perldbmfilter&gt;, L&lt;Fcntl&gt;

=cut
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