zip.pm

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The default method is ZIP_CM_DEFLATE.

=item C<< Stream => 0|1 >>

This option controls whether the zip file/buffer output is created in
streaming mode.

Note that when outputting to a file with streaming mode disabled (C<Stream>
is 0), the output file must be seekable.

The default is 1.

=item C<< Zip64 => 0|1 >>

Create a Zip64 zip file/buffer. This option should only be used if you want
to store files larger than 4 Gig.

If you intend to manipulate the Zip64 zip files created with this module
using an external zip/unzip make sure that it supports streaming Zip64.  

In particular, if you are using Info-Zip you need to have zip version 3.x
or better to update a Zip64 archive and unzip version 6.x to read a zip64
archive. At the time of writing both are beta status.

When the C<Zip64> option is enabled, the C<Stream> option I<must> be
enabled as well.

The default is 0.

=item C<< TextFlag => 0|1 >>

This parameter controls the setting of a bit in the zip central header. It
is used to signal that the data stored in the zip file/buffer is probably
text.

The default is 0. 

=item C<< ExtraFieldLocal => $data >>
=item C<< ExtraFieldCentral => $data >>

These options allows additional metadata to be stored in the local and
central headers in the zip file/buffer.

An extra field consists of zero or more subfields. Each subfield consists
of a two byte header followed by the subfield data.

The list of subfields can be supplied in any of the following formats

    ExtraFieldLocal => [$id1, $data1,
                        $id2, $data2,
                         ...
                       ]

    ExtraFieldLocal => [ [$id1 => $data1],
                         [$id2 => $data2],
                         ...
                       ]

    ExtraFieldLocal => { $id1 => $data1,
                         $id2 => $data2,
                         ...
                       }

Where C<$id1>, C<$id2> are two byte subfield ID's. 

If you use the hash syntax, you have no control over the order in which
the ExtraSubFields are stored, plus you cannot have SubFields with
duplicate ID.

Alternatively the list of subfields can by supplied as a scalar, thus

    ExtraField => $rawdata

The Extended Time field, set using the C<exTime> option, is an example of
an extended field.



If the C<Minimal> option is set to true, this option will be ignored.

The maximum size of an extra field 65535 bytes.

=item C<< Minimal => 1|0 >>

If specified, this option will disable the creation of all extended fields
in the zip local and central headers. So the C<exTime>, C<ExtraFieldLocal>
and C<ExtraFieldCentral> options will be ignored.

This parameter defaults to 0.

=item C<< BlockSize100K => number >>

Specify the number of 100K blocks bzip2 uses during compression. 

Valid values are from 1 to 9, where 9 is best compression.

This option is only valid if the C<Method> is ZIP_CM_BZIP2. It is ignored
otherwise.

The default is 1.

=item C<< WorkFactor => number >>

Specifies how much effort bzip2 should take before resorting to a slower
fallback compression algorithm.

Valid values range from 0 to 250, where 0 means use the default value 30.

This option is only valid if the C<Method> is ZIP_CM_BZIP2. It is ignored
otherwise.

The default is 0.




=item -Level 

Defines the compression level used by zlib. The value should either be
a number between 0 and 9 (0 means no compression and 9 is maximum
compression), or one of the symbolic constants defined below.

   Z_NO_COMPRESSION
   Z_BEST_SPEED
   Z_BEST_COMPRESSION
   Z_DEFAULT_COMPRESSION

The default is Z_DEFAULT_COMPRESSION.

Note, these constants are not imported by C<IO::Compress::Zip> by default.

    use IO::Compress::Zip qw(:strategy);
    use IO::Compress::Zip qw(:constants);
    use IO::Compress::Zip qw(:all);

=item -Strategy 

Defines the strategy used to tune the compression. Use one of the symbolic
constants defined below.

   Z_FILTERED
   Z_HUFFMAN_ONLY
   Z_RLE
   Z_FIXED
   Z_DEFAULT_STRATEGY

The default is Z_DEFAULT_STRATEGY.






=item C<< Strict => 0|1 >>



This is a placeholder option.



=back

=head2 Examples

TODO

=head1 Methods 

=head2 print

Usage is

    $z->print($data)
    print $z $data

Compresses and outputs the contents of the C<$data> parameter. This
has the same behaviour as the C<print> built-in.

Returns true if successful.

=head2 printf

Usage is

    $z->printf($format, $data)
    printf $z $format, $data

Compresses and outputs the contents of the C<$data> parameter.

Returns true if successful.

=head2 syswrite

Usage is

    $z->syswrite $data
    $z->syswrite $data, $length
    $z->syswrite $data, $length, $offset

Compresses and outputs the contents of the C<$data> parameter.

Returns the number of uncompressed bytes written, or C<undef> if
unsuccessful.

=head2 write

Usage is

    $z->write $data
    $z->write $data, $length
    $z->write $data, $length, $offset

Compresses and outputs the contents of the C<$data> parameter.

Returns the number of uncompressed bytes written, or C<undef> if
unsuccessful.

=head2 flush

Usage is


    $z->flush;
    $z->flush($flush_type);


Flushes any pending compressed data to the output file/buffer.


This method takes an optional parameter, C<$flush_type>, that controls
how the flushing will be carried out. By default the C<$flush_type>
used is C<Z_FINISH>. Other valid values for C<$flush_type> are
C<Z_NO_FLUSH>, C<Z_SYNC_FLUSH>, C<Z_FULL_FLUSH> and C<Z_BLOCK>. It is
strongly recommended that you only set the C<flush_type> parameter if
you fully understand the implications of what it does - overuse of C<flush>
can seriously degrade the level of compression achieved. See the C<zlib>
documentation for details.


Returns true on success.


=head2 tell

Usage is

    $z->tell()
    tell $z

Returns the uncompressed file offset.

=head2 eof

Usage is

    $z->eof();
    eof($z);



Returns true if the C<close> method has been called.



=head2 seek

    $z->seek($position, $whence);
    seek($z, $position, $whence);




Provides a sub-set of the C<seek> functionality, with the restriction
that it is only legal to seek forward in the output file/buffer.
It is a fatal error to attempt to seek backward.

Empty parts of the file/buffer will have NULL (0x00) bytes written to them.



The C<$whence> parameter takes one the usual values, namely SEEK_SET,
SEEK_CUR or SEEK_END.

Returns 1 on success, 0 on failure.

=head2 binmode

Usage is

    $z->binmode
    binmode $z ;

This is a noop provided for completeness.

=head2 opened

    $z->opened()

Returns true if the object currently refers to a opened file/buffer. 

=head2 autoflush

    my $prev = $z->autoflush()
    my $prev = $z->autoflush(EXPR)

If the C<$z> object is associated with a file or a filehandle, this method
returns the current autoflush setting for the underlying filehandle. If
C<EXPR> is present, and is non-zero, it will enable flushing after every
write/print operation.

If C<$z> is associated with a buffer, this method has no effect and always
returns C<undef>.

B<Note> that the special variable C<$|> B<cannot> be used to set or
retrieve the autoflush setting.

=head2 input_line_number

    $z->input_line_number()
    $z->input_line_number(EXPR)


This method always returns C<undef> when compressing. 



=head2 fileno

    $z->fileno()
    fileno($z)

If the C<$z> object is associated with a file or a filehandle, this method
will return the underlying file descriptor.

If the C<$z> object is is associated with a buffer, this method will
return undef.

=head2 close

    $z->close() ;
    close $z ;



Flushes any pending compressed data and then closes the output file/buffer. 



For most versions of Perl this method will be automatically invoked if
the IO::Compress::Zip object is destroyed (either explicitly or by the
variable with the reference to the object going out of scope). The
exceptions are Perl versions 5.005 through 5.00504 and 5.8.0. In
these cases, the C<close> method will be called automatically, but
not until global destruction of all live objects when the program is
terminating.

Therefore, if you want your scripts to be able to run on all versions
of Perl, you should call C<close> explicitly and not rely on automatic
closing.

Returns true on success, otherwise 0.

If the C<AutoClose> option has been enabled when the IO::Compress::Zip
object was created, and the object is associated with a file, the
underlying file will also be closed.




=head2 newStream([OPTS])

Usage is

    $z->newStream( [OPTS] )

Closes the current compressed data stream and starts a new one.

OPTS consists of any of the the options that are available when creating
the C<$z> object.

See the L</"Constructor Options"> section for more details.


=head2 deflateParams

Usage is

    $z->deflateParams

TODO


=head1 Importing 


A number of symbolic constants are required by some methods in 
C<IO::Compress::Zip>. None are imported by default.



=over 5

=item :all


Imports C<zip>, C<$ZipError> and all symbolic
constants that can be used by C<IO::Compress::Zip>. Same as doing this

    use IO::Compress::Zip qw(zip $ZipError :constants) ;

=item :constants

Import all symbolic constants. Same as doing this


    use IO::Compress::Zip qw(:flush :level :strategy :zip_method) ;


=item :flush

These symbolic constants are used by the C<flush> method.

    Z_NO_FLUSH
    Z_PARTIAL_FLUSH
    Z_SYNC_FLUSH
    Z_FULL_FLUSH
    Z_FINISH
    Z_BLOCK

=item :level

These symbolic constants are used by the C<Level> option in the constructor.

    Z_NO_COMPRESSION
    Z_BEST_SPEED
    Z_BEST_COMPRESSION
    Z_DEFAULT_COMPRESSION


=item :strategy

These symbolic constants are used by the C<Strategy> option in the constructor.

    Z_FILTERED
    Z_HUFFMAN_ONLY
    Z_RLE
    Z_FIXED
    Z_DEFAULT_STRATEGY


=item :zip_method

These symbolic constants are used by the C<Method> option in the
constructor.

    ZIP_CM_STORE
    ZIP_CM_DEFLATE
    ZIP_CM_BZIP2

    
    

=back

For 

=head1 EXAMPLES

TODO











=head1 SEE ALSO

L<Compress::Zlib>, L<IO::Compress::Gzip>, L<IO::Uncompress::Gunzip>, L<IO::Compress::Deflate>, L<IO::Uncompress::Inflate>, L<IO::Compress::RawDeflate>, L<IO::Uncompress::RawInflate>, L<IO::Compress::Bzip2>, L<IO::Uncompress::Bunzip2>, L<IO::Compress::Lzop>, L<IO::Uncompress::UnLzop>, L<IO::Compress::Lzf>, L<IO::Uncompress::UnLzf>, L<IO::Uncompress::AnyInflate>, L<IO::Uncompress::AnyUncompress>

L<Compress::Zlib::FAQ|Compress::Zlib::FAQ>

L<File::GlobMapper|File::GlobMapper>, L<Archive::Zip|Archive::Zip>,
L<Archive::Tar|Archive::Tar>,
L<IO::Zlib|IO::Zlib>


For RFC 1950, 1951 and 1952 see 
F<http://www.faqs.org/rfcs/rfc1950.html>,
F<http://www.faqs.org/rfcs/rfc1951.html> and
F<http://www.faqs.org/rfcs/rfc1952.html>

The I<zlib> compression library was written by Jean-loup Gailly
F<[e-mail]> and Mark Adler F<[e-mail]>.

The primary site for the I<zlib> compression library is
F<http://www.zlib.org>.

The primary site for gzip is F<http://www.gzip.org>.




=head1 AUTHOR

This module was written by Paul Marquess, F<[e-mail]>. 



=head1 MODIFICATION HISTORY

See the Changes file.

=head1 COPYRIGHT AND LICENSE

Copyright (c) 2005-2007 Paul Marquess. All rights reserved.

This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.