path: root/upstream/debian-unstable/man3/IO::Compress::Zip.3perl

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.\" ========================================================================
.\"
.IX Title "IO::Compress::Zip 3perl"
.TH IO::Compress::Zip 3perl 2024-01-12 "perl v5.38.2" "Perl Programmers Reference Guide"
.\" For nroff, turn off justification.  Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH NAME
IO::Compress::Zip \- Write zip files/buffers
.SH SYNOPSIS
.IX Header "SYNOPSIS"
.Vb 1
\&    use IO::Compress::Zip qw(zip $ZipError) ;
\&
\&    my $status = zip $input => $output [,OPTS]
\&        or die "zip failed: $ZipError\en";
\&
\&    my $z = IO::Compress::Zip\->new( $output [,OPTS] )
\&        or die "zip failed: $ZipError\en";
\&
\&    $z\->print($string);
\&    $z\->printf($format, $string);
\&    $z\->write($string);
\&    $z\->syswrite($string [, $length, $offset]);
\&    $z\->flush();
\&    $z\->tell();
\&    $z\->eof();
\&    $z\->seek($position, $whence);
\&    $z\->binmode();
\&    $z\->fileno();
\&    $z\->opened();
\&    $z\->autoflush();
\&    $z\->input_line_number();
\&    $z\->newStream( [OPTS] );
\&
\&    $z\->deflateParams();
\&
\&    $z\->close() ;
\&
\&    $ZipError ;
\&
\&    # IO::File mode
\&
\&    print $z $string;
\&    printf $z $format, $string;
\&    tell $z
\&    eof $z
\&    seek $z, $position, $whence
\&    binmode $z
\&    fileno $z
\&    close $z ;
.Ve
.SH DESCRIPTION
.IX Header "DESCRIPTION"
This module provides a Perl interface that allows writing zip
compressed data to files or buffer.
.PP
The primary purpose of this module is to provide streaming write access to
zip files and buffers.
.PP
At present the following compression methods are supported by IO::Compress::Zip
.IP "Store (0)" 5
.IX Item "Store (0)"
.PD 0
.IP "Deflate (8)" 5
.IX Item "Deflate (8)"
.IP "Bzip2 (12)" 5
.IX Item "Bzip2 (12)"
.PD
To write Bzip2 content, the module \f(CW\*(C`IO::Uncompress::Bunzip2\*(C'\fR must
be installed.
.IP "Lzma (14)" 5
.IX Item "Lzma (14)"
To write LZMA content, the module \f(CW\*(C`IO::Uncompress::UnLzma\*(C'\fR must
be installed.
.IP "Zstandard (93)" 5
.IX Item "Zstandard (93)"
To write Zstandard content, the module \f(CW\*(C`IO::Compress::Zstd\*(C'\fR must
be installed.
.IP "Xz (95)" 5
.IX Item "Xz (95)"
To write Xz content, the module \f(CW\*(C`IO::Uncompress::UnXz\*(C'\fR must
be installed.
.PP
For reading zip files/buffers, see the companion module
IO::Uncompress::Unzip.
.SH "Functional Interface"
.IX Header "Functional Interface"
A top-level function, \f(CW\*(C`zip\*(C'\fR, is provided to carry out
"one-shot" compression between buffers and/or files. For finer
control over the compression process, see the "OO Interface"
section.
.PP
.Vb 1
\&    use IO::Compress::Zip qw(zip $ZipError) ;
\&
\&    zip $input_filename_or_reference => $output_filename_or_reference [,OPTS]
\&        or die "zip failed: $ZipError\en";
.Ve
.PP
The functional interface needs Perl5.005 or better.
.ie n .SS "zip $input_filename_or_reference => $output_filename_or_reference [, OPTS]"
.el .SS "zip \f(CW$input_filename_or_reference\fP => \f(CW$output_filename_or_reference\fP [, OPTS]"
.IX Subsection "zip $input_filename_or_reference => $output_filename_or_reference [, OPTS]"
\&\f(CW\*(C`zip\*(C'\fR expects at least two parameters,
\&\f(CW$input_filename_or_reference\fR and \f(CW$output_filename_or_reference\fR
and zero or more optional parameters (see "Optional Parameters")
.PP
\fIThe \fR\f(CI$input_filename_or_reference\fR\fI parameter\fR
.IX Subsection "The $input_filename_or_reference parameter"
.PP
The parameter, \f(CW$input_filename_or_reference\fR, is used to define the
source of the uncompressed data.
.PP
It can take one of the following forms:
.IP "A filename" 5
.IX Item "A filename"
If the \f(CW$input_filename_or_reference\fR parameter is a simple scalar, it is
assumed to be a filename. This file will be opened for reading and the
input data will be read from it.
.IP "A filehandle" 5
.IX Item "A filehandle"
If the \f(CW$input_filename_or_reference\fR parameter is a filehandle, the input
data will be read from it.  The string '\-' can be used as an alias for
standard input.
.IP "A scalar reference" 5
.IX Item "A scalar reference"
If \f(CW$input_filename_or_reference\fR is a scalar reference, the input data
will be read from \f(CW$$input_filename_or_reference\fR.
.IP "An array reference" 5
.IX Item "An array reference"
If \f(CW$input_filename_or_reference\fR is an array reference, each element in
the array must be a filename.
.Sp
The input data will be read from each file in turn.
.Sp
The complete array will be walked to ensure that it only
contains valid filenames before any data is compressed.
.IP "An Input FileGlob string" 5
.IX Item "An Input FileGlob string"
If \f(CW$input_filename_or_reference\fR is a string that is delimited by the
characters "<" and ">" \f(CW\*(C`zip\*(C'\fR will assume that it is an
\&\fIinput fileglob string\fR. The input is the list of files that match the
fileglob.
.Sp
See File::GlobMapper for more details.
.PP
If the \f(CW$input_filename_or_reference\fR parameter is any other type,
\&\f(CW\*(C`undef\*(C'\fR will be returned.
.PP
In addition, if \f(CW$input_filename_or_reference\fR corresponds to a filename
from the filesystem, a number of zip file header fields will be populated by default
using the following attributes from the input file
.IP \(bu 5
the full filename contained in \f(CW$input_filename_or_reference\fR
.IP \(bu 5
the file protection attributes
.IP \(bu 5
the UID/GID for the file
.IP \(bu 5
the file timestamps
.PP
If you do not want to use these defaults they can be overridden by
explicitly setting one, or more, of the \f(CW\*(C`Name\*(C'\fR, \f(CW\*(C`Time\*(C'\fR, \f(CW\*(C`TextFlag\*(C'\fR, \f(CW\*(C`ExtAttr\*(C'\fR, \f(CW\*(C`exUnixN\*(C'\fR and \f(CW\*(C`exTime\*(C'\fR options or by setting the
\&\f(CW\*(C`Minimal\*(C'\fR parameter.
.PP
\fIThe \fR\f(CI$output_filename_or_reference\fR\fI parameter\fR
.IX Subsection "The $output_filename_or_reference parameter"
.PP
The parameter \f(CW$output_filename_or_reference\fR is used to control the
destination of the compressed data. This parameter can take one of
these forms.
.IP "A filename" 5
.IX Item "A filename"
If the \f(CW$output_filename_or_reference\fR parameter is a simple scalar, it is
assumed to be a filename.  This file will be opened for writing and the
compressed data will be written to it.
.IP "A filehandle" 5
.IX Item "A filehandle"
If the \f(CW$output_filename_or_reference\fR parameter is a filehandle, the
compressed data will be written to it.  The string '\-' can be used as
an alias for standard output.
.IP "A scalar reference" 5
.IX Item "A scalar reference"
If \f(CW$output_filename_or_reference\fR is a scalar reference, the
compressed data will be stored in \f(CW$$output_filename_or_reference\fR.
.IP "An Array Reference" 5
.IX Item "An Array Reference"
If \f(CW$output_filename_or_reference\fR is an array reference,
the compressed data will be pushed onto the array.
.IP "An Output FileGlob" 5
.IX Item "An Output FileGlob"
If \f(CW$output_filename_or_reference\fR is a string that is delimited by the
characters "<" and ">" \f(CW\*(C`zip\*(C'\fR will assume that it is an
\&\fIoutput fileglob string\fR. The output is the list of files that match the
fileglob.
.Sp
When \f(CW$output_filename_or_reference\fR is an fileglob string,
\&\f(CW$input_filename_or_reference\fR must also be a fileglob string. Anything
else is an error.
.Sp
See File::GlobMapper for more details.
.PP
If the \f(CW$output_filename_or_reference\fR parameter is any other type,
\&\f(CW\*(C`undef\*(C'\fR will be returned.
.SS Notes
.IX Subsection "Notes"
When \f(CW$input_filename_or_reference\fR maps to multiple files/buffers and
\&\f(CW$output_filename_or_reference\fR is a single
file/buffer the input files/buffers will each be stored
in \f(CW$output_filename_or_reference\fR as a distinct entry.
.SS "Optional Parameters"
.IX Subsection "Optional Parameters"
The optional parameters for the one-shot function \f(CW\*(C`zip\*(C'\fR
are (for the most part) identical to those used with the OO interface defined in the
"Constructor Options" section. The exceptions are listed below
.ie n .IP """AutoClose => 0|1""" 5
.el .IP "\f(CWAutoClose => 0|1\fR" 5
.IX Item "AutoClose => 0|1"
This option applies to any input or output data streams to
\&\f(CW\*(C`zip\*(C'\fR that are filehandles.
.Sp
If \f(CW\*(C`AutoClose\*(C'\fR is specified, and the value is true, it will result in all
input and/or output filehandles being closed once \f(CW\*(C`zip\*(C'\fR has
completed.
.Sp
This parameter defaults to 0.
.ie n .IP """BinModeIn => 0|1""" 5
.el .IP "\f(CWBinModeIn => 0|1\fR" 5
.IX Item "BinModeIn => 0|1"
This option is now a no-op. All files will be read in binmode.
.ie n .IP """Append => 0|1""" 5
.el .IP "\f(CWAppend => 0|1\fR" 5
.IX Item "Append => 0|1"
The behaviour of this option is dependent on the type of output data
stream.
.RS 5
.IP \(bu 5
A Buffer
.Sp
If \f(CW\*(C`Append\*(C'\fR is enabled, all compressed data will be append to the end of
the output buffer. Otherwise the output buffer will be cleared before any
compressed data is written to it.
.IP \(bu 5
A Filename
.Sp
If \f(CW\*(C`Append\*(C'\fR is enabled, the file will be opened in append mode. Otherwise
the contents of the file, if any, will be truncated before any compressed
data is written to it.
.IP \(bu 5
A Filehandle
.Sp
If \f(CW\*(C`Append\*(C'\fR is enabled, the filehandle will be positioned to the end of
the file via a call to \f(CW\*(C`seek\*(C'\fR before any compressed data is
written to it.  Otherwise the file pointer will not be moved.
.RE
.RS 5
.Sp
When \f(CW\*(C`Append\*(C'\fR is specified, and set to true, it will \fIappend\fR all compressed
data to the output data stream.
.Sp
So when the output is a filehandle it will carry out a seek to the eof
before writing any compressed data. If the output is a filename, it will be opened for
appending. If the output is a buffer, all compressed data will be
appended to the existing buffer.
.Sp
Conversely when \f(CW\*(C`Append\*(C'\fR is not specified, or it is present and is set to
false, it will operate as follows.
.Sp
When the output is a filename, it will truncate the contents of the file
before writing any compressed data. If the output is a filehandle
its position will not be changed. If the output is a buffer, it will be
wiped before any compressed data is output.
.Sp
Defaults to 0.
.RE
.SS Examples
.IX Subsection "Examples"
Here are a few example that show the capabilities of the module.
.PP
\fIStreaming\fR
.IX Subsection "Streaming"
.PP
This very simple command line example demonstrates the streaming capabilities of the module.
The code reads data from STDIN, compresses it, and writes the compressed data to STDOUT.
.PP
.Vb 1
\&    $ echo hello world | perl \-MIO::Compress::Zip=zip \-e \*(Aqzip \e*STDIN => \e*STDOUT\*(Aq >output.zip
.Ve
.PP
The special filename "\-" can be used as a standin for both \f(CW\*(C`\e*STDIN\*(C'\fR and \f(CW\*(C`\e*STDOUT\*(C'\fR,
so the above can be rewritten as
.PP
.Vb 1
\&    $ echo hello world | perl \-MIO::Compress::Zip=zip \-e \*(Aqzip "\-" => "\-"\*(Aq >output.zip
.Ve
.PP
One problem with creating a zip archive directly from STDIN can be demonstrated by looking at
the contents of the zip file, output.zip, that we have just created.
.PP
.Vb 7
\&    $ unzip \-l output.zip
\&    Archive:  output.zip
\&    Length      Date    Time    Name
\&    \-\-\-\-\-\-\-\-\-  \-\-\-\-\-\-\-\-\-\- \-\-\-\-\-   \-\-\-\-
\&        12  2019\-08\-16 22:21
\&    \-\-\-\-\-\-\-\-\-                     \-\-\-\-\-\-\-
\&        12                     1 file
.Ve
.PP
The archive member (filename) used is the empty string.
.PP
If that doesn't suit your needs, you can explicitly set the filename used
in the zip archive by specifying the Name option, like so
.PP
.Vb 1
\&    echo hello world | perl \-MIO::Compress::Zip=zip \-e \*(Aqzip "\-" => "\-", Name => "hello.txt"\*(Aq >output.zip
.Ve
.PP
Now the contents of the zip file looks like this
.PP
.Vb 7
\&    $ unzip \-l output.zip
\&    Archive:  output.zip
\&    Length      Date    Time    Name
\&    \-\-\-\-\-\-\-\-\-  \-\-\-\-\-\-\-\-\-\- \-\-\-\-\-   \-\-\-\-
\&        12  2019\-08\-16 22:22   hello.txt
\&    \-\-\-\-\-\-\-\-\-                     \-\-\-\-\-\-\-
\&        12                     1 file
.Ve
.PP
\fICompressing a file from the filesystem\fR
.IX Subsection "Compressing a file from the filesystem"
.PP
To read the contents of the file \f(CW\*(C`file1.txt\*(C'\fR and write the compressed
data to the file \f(CW\*(C`file1.txt.zip\*(C'\fR.
.PP
.Vb 3
\&    use strict ;
\&    use warnings ;
\&    use IO::Compress::Zip qw(zip $ZipError) ;
\&
\&    my $input = "file1.txt";
\&    zip $input => "$input.zip"
\&        or die "zip failed: $ZipError\en";
.Ve
.PP
\fIReading from a Filehandle and writing to an in-memory buffer\fR
.IX Subsection "Reading from a Filehandle and writing to an in-memory buffer"
.PP
To read from an existing Perl filehandle, \f(CW$input\fR, and write the
compressed data to a buffer, \f(CW$buffer\fR.
.PP
.Vb 4
\&    use strict ;
\&    use warnings ;
\&    use IO::Compress::Zip qw(zip $ZipError) ;
\&    use IO::File ;
\&
\&    my $input = IO::File\->new( "<file1.txt" )
\&        or die "Cannot open \*(Aqfile1.txt\*(Aq: $!\en" ;
\&    my $buffer ;
\&    zip $input => \e$buffer
\&        or die "zip failed: $ZipError\en";
.Ve
.PP
\fICompressing multiple files\fR
.IX Subsection "Compressing multiple files"
.PP
To create a zip file, \f(CW\*(C`output.zip\*(C'\fR, that contains the compressed contents
of the files \f(CW\*(C`alpha.txt\*(C'\fR and \f(CW\*(C`beta.txt\*(C'\fR
.PP
.Vb 3
\&    use strict ;
\&    use warnings ;
\&    use IO::Compress::Zip qw(zip $ZipError) ;
\&
\&    zip [ \*(Aqalpha.txt\*(Aq, \*(Aqbeta.txt\*(Aq ] => \*(Aqoutput.zip\*(Aq
\&        or die "zip failed: $ZipError\en";
.Ve
.PP
Alternatively, rather than having to explicitly name each of the files that
you want to compress, you could use a fileglob to select all the \f(CW\*(C`txt\*(C'\fR
files in the current directory, as follows
.PP
.Vb 3
\&    use strict ;
\&    use warnings ;
\&    use IO::Compress::Zip qw(zip $ZipError) ;
\&
\&    my @files = <*.txt>;
\&    zip \e@files => \*(Aqoutput.zip\*(Aq
\&        or die "zip failed: $ZipError\en";
.Ve
.PP
or more succinctly
.PP
.Vb 2
\&    zip [ <*.txt> ] => \*(Aqoutput.zip\*(Aq
\&        or die "zip failed: $ZipError\en";
.Ve
.SH "OO Interface"
.IX Header "OO Interface"
.SS Constructor
.IX Subsection "Constructor"
The format of the constructor for \f(CW\*(C`IO::Compress::Zip\*(C'\fR is shown below
.PP
.Vb 2
\&    my $z = IO::Compress::Zip\->new( $output [,OPTS] )
\&        or die "IO::Compress::Zip failed: $ZipError\en";
.Ve
.PP
It returns an \f(CW\*(C`IO::Compress::Zip\*(C'\fR object on success and undef on failure.
The variable \f(CW$ZipError\fR will contain an error message on failure.
.PP
If you are running Perl 5.005 or better the object, \f(CW$z\fR, returned from
IO::Compress::Zip can be used exactly like an IO::File filehandle.
This means that all normal output file operations can be carried out
with \f(CW$z\fR.
For example, to write to a compressed file/buffer you can use either of
these forms
.PP
.Vb 2
\&    $z\->print("hello world\en");
\&    print $z "hello world\en";
.Ve
.PP
The mandatory parameter \f(CW$output\fR is used to control the destination
of the compressed data. This parameter can take one of these forms.
.IP "A filename" 5
.IX Item "A filename"
If the \f(CW$output\fR parameter is a simple scalar, it is assumed to be a
filename. This file will be opened for writing and the compressed data
will be written to it.
.IP "A filehandle" 5
.IX Item "A filehandle"
If the \f(CW$output\fR parameter is a filehandle, the compressed data will be
written to it.
The string '\-' can be used as an alias for standard output.
.IP "A scalar reference" 5
.IX Item "A scalar reference"
If \f(CW$output\fR is a scalar reference, the compressed data will be stored
in \f(CW$$output\fR.
.PP
If the \f(CW$output\fR parameter is any other type, \f(CW\*(C`IO::Compress::Zip\*(C'\fR::new will
return undef.
.SS "Constructor Options"
.IX Subsection "Constructor Options"
\&\f(CW\*(C`OPTS\*(C'\fR is any combination of zero or more the following options:
.ie n .IP """AutoClose => 0|1""" 5
.el .IP "\f(CWAutoClose => 0|1\fR" 5
.IX Item "AutoClose => 0|1"
This option is only valid when the \f(CW$output\fR parameter is a filehandle. If
specified, and the value is true, it will result in the \f(CW$output\fR being
closed once either the \f(CW\*(C`close\*(C'\fR method is called or the \f(CW\*(C`IO::Compress::Zip\*(C'\fR
object is destroyed.
.Sp
This parameter defaults to 0.
.ie n .IP """Append => 0|1""" 5
.el .IP "\f(CWAppend => 0|1\fR" 5
.IX Item "Append => 0|1"
Opens \f(CW$output\fR in append mode.
.Sp
The behaviour of this option is dependent on the type of \f(CW$output\fR.
.RS 5
.IP \(bu 5
A Buffer
.Sp
If \f(CW$output\fR is a buffer and \f(CW\*(C`Append\*(C'\fR is enabled, all compressed data
will be append to the end of \f(CW$output\fR. Otherwise \f(CW$output\fR will be
cleared before any data is written to it.
.IP \(bu 5
A Filename
.Sp
If \f(CW$output\fR is a filename and \f(CW\*(C`Append\*(C'\fR is enabled, the file will be
opened in append mode. Otherwise the contents of the file, if any, will be
truncated before any compressed data is written to it.
.IP \(bu 5
A Filehandle
.Sp
If \f(CW$output\fR is a filehandle, the file pointer will be positioned to the
end of the file via a call to \f(CW\*(C`seek\*(C'\fR before any compressed data is written
to it.  Otherwise the file pointer will not be moved.
.RE
.RS 5
.Sp
This parameter defaults to 0.
.RE
.PP
\fIFile Naming Options\fR
.IX Subsection "File Naming Options"
.PP
A quick bit of zip file terminology \-\- A zip archive consists of one or more \fIarchive members\fR, where each member has an associated
filename, known as the \fIarchive member name\fR.
.PP
The options listed in this section control how the \fIarchive member name\fR (or filename) is stored the zip archive.
.ie n .IP """Name => $string""" 5
.el .IP "\f(CWName => $string\fR" 5
.IX Item "Name => $string"
This option is used to explicitly set the \fIarchive member name\fR in
the zip archive to \f(CW$string\fR.
Most of the time you don't need to make use of this option.
By default when adding a filename to the zip archive, the \fIarchive member name\fR will match the filename.
.Sp
You should only need to use this option if you want the \fIarchive member name\fR
to be different from the uncompressed filename or when the input is a filehandle or a buffer.
.Sp
The default behaviour for what \fIarchive member name\fR is used when the \f(CW\*(C`Name\*(C'\fR option
is \fInot\fR specified depends on the form of the \f(CW$input\fR parameter:
.RS 5
.IP \(bu 5
If the \f(CW$input\fR parameter is a filename, the
value of \f(CW$input\fR will be used for the \fIarchive member name\fR .
.IP \(bu 5
If the \f(CW$input\fR parameter is not a filename,
the \fIarchive member name\fR will be an empty string.
.RE
.RS 5
.Sp
Note that both the \f(CW\*(C`CanonicalName\*(C'\fR and \f(CW\*(C`FilterName\*(C'\fR options
can modify the value used for the \fIarchive member name\fR.
.Sp
Also note that you should set the \f(CW\*(C`Efs\*(C'\fR option to true if you are working
with UTF8 filenames.
.RE
.ie n .IP """CanonicalName => 0|1""" 5
.el .IP "\f(CWCanonicalName => 0|1\fR" 5
.IX Item "CanonicalName => 0|1"
This option controls whether the \fIarchive member name\fR is
\&\fInormalized\fR into Unix format before being written to the zip file.
.Sp
It is recommended that you enable this option unless you really need
to create a non-standard Zip file.
.Sp
This is what APPNOTE.TXT has to say on what should be stored in the zip
filename header field.
.Sp
.Vb 6
\&    The name of the file, with optional relative path.
\&    The path stored should not contain a drive or
\&    device letter, or a leading slash.  All slashes
\&    should be forward slashes \*(Aq/\*(Aq as opposed to
\&    backwards slashes \*(Aq\e\*(Aq for compatibility with Amiga
\&    and UNIX file systems etc.
.Ve
.Sp
This option defaults to \fBfalse\fR.
.ie n .IP """FilterName => sub { ... }""" 5
.el .IP "\f(CWFilterName => sub { ... }\fR" 5
.IX Item "FilterName => sub { ... }"
This option allow the \fIarchive member\fR name to be modified
before it is written to the zip file.
.Sp
This option takes a parameter that must be a reference to a sub.  On entry
to the sub the \f(CW$_\fR variable will contain the name to be filtered. If no
filename is available \f(CW$_\fR will contain an empty string.
.Sp
The value of \f(CW$_\fR when the sub returns will be  used as the \fIarchive member name\fR.
.Sp
Note that if \f(CW\*(C`CanonicalName\*(C'\fR is enabled, a
normalized filename will be passed to the sub.
.Sp
If you use \f(CW\*(C`FilterName\*(C'\fR to modify the filename, it is your responsibility
to keep the filename in Unix format.
.Sp
Although this option can be used with the OO interface, it is of most use
with the one-shot interface. For example, the code below shows how
\&\f(CW\*(C`FilterName\*(C'\fR can be used to remove the path component from a series of
filenames before they are stored in \f(CW$zipfile\fR.
.Sp
.Vb 4
\&    sub compressTxtFiles
\&    {
\&        my $zipfile = shift ;
\&        my $dir     = shift ;
\&
\&        zip [ <$dir/*.txt> ] => $zipfile,
\&            FilterName => sub { s[^$dir/][] } ;
\&    }
.Ve
.ie n .IP """Efs => 0|1""" 5
.el .IP "\f(CWEfs => 0|1\fR" 5
.IX Item "Efs => 0|1"
This option controls setting of the "Language Encoding Flag" (EFS) in the zip
archive. When set, the filename and comment fields for the zip archive MUST
be valid UTF\-8.
.Sp
If the string used for the filename and/or comment is not valid UTF\-8 when this option
is true, the script will die with a "wide character" error.
.Sp
Note that this option only works with Perl 5.8.4 or better.
.Sp
This option defaults to \fBfalse\fR.
.PP
\fIOverall Zip Archive Structure\fR
.IX Subsection "Overall Zip Archive Structure"
.ie n .IP """Minimal => 1|0""" 5
.el .IP "\f(CWMinimal => 1|0\fR" 5
.IX Item "Minimal => 1|0"
If specified, this option will disable the creation of all extra fields
in the zip local and central headers. So the \f(CW\*(C`exTime\*(C'\fR, \f(CW\*(C`exUnix2\*(C'\fR,
\&\f(CW\*(C`exUnixN\*(C'\fR, \f(CW\*(C`ExtraFieldLocal\*(C'\fR and \f(CW\*(C`ExtraFieldCentral\*(C'\fR options will
be ignored.
.Sp
This parameter defaults to 0.
.ie n .IP """Stream => 0|1""" 5
.el .IP "\f(CWStream => 0|1\fR" 5
.IX Item "Stream => 0|1"
This option controls whether the zip file/buffer output is created in
streaming mode.
.Sp
Note that when outputting to a file with streaming mode disabled (\f(CW\*(C`Stream\*(C'\fR
is 0), the output file must be seekable.
.Sp
The default is 1.
.ie n .IP """Zip64 => 0|1""" 5
.el .IP "\f(CWZip64 => 0|1\fR" 5
.IX Item "Zip64 => 0|1"
Create a Zip64 zip file/buffer. This option is used if you want
to store files larger than 4 Gig or store more than 64K files in a single
zip archive.
.Sp
\&\f(CW\*(C`Zip64\*(C'\fR will be automatically set, as needed, if working with the one-shot
interface when the input is either a filename or a scalar reference.
.Sp
If you intend to manipulate the Zip64 zip files created with this module
using an external zip/unzip, make sure that it supports Zip64.
.Sp
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.
.Sp
The default is 0.
.PP
\fIDeflate Compression Options\fR
.IX Subsection "Deflate Compression Options"
.IP \-Level 5
.IX 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.
.Sp
.Vb 4
\&   Z_NO_COMPRESSION
\&   Z_BEST_SPEED
\&   Z_BEST_COMPRESSION
\&   Z_DEFAULT_COMPRESSION
.Ve
.Sp
The default is Z_DEFAULT_COMPRESSION.
.Sp
Note, these constants are not imported by \f(CW\*(C`IO::Compress::Zip\*(C'\fR by default.
.Sp
.Vb 3
\&    use IO::Compress::Zip qw(:strategy);
\&    use IO::Compress::Zip qw(:constants);
\&    use IO::Compress::Zip qw(:all);
.Ve
.IP \-Strategy 5
.IX Item "-Strategy"
Defines the strategy used to tune the compression. Use one of the symbolic
constants defined below.
.Sp
.Vb 5
\&   Z_FILTERED
\&   Z_HUFFMAN_ONLY
\&   Z_RLE
\&   Z_FIXED
\&   Z_DEFAULT_STRATEGY
.Ve
.Sp
The default is Z_DEFAULT_STRATEGY.
.PP
\fIBzip2 Compression Options\fR
.IX Subsection "Bzip2 Compression Options"
.ie n .IP """BlockSize100K => number""" 5
.el .IP "\f(CWBlockSize100K => number\fR" 5
.IX Item "BlockSize100K => number"
Specify the number of 100K blocks bzip2 uses during compression.
.Sp
Valid values are from 1 to 9, where 9 is best compression.
.Sp
This option is only valid if the \f(CW\*(C`Method\*(C'\fR is ZIP_CM_BZIP2. It is ignored
otherwise.
.Sp
The default is 1.
.ie n .IP """WorkFactor => number""" 5
.el .IP "\f(CWWorkFactor => number\fR" 5
.IX Item "WorkFactor => number"
Specifies how much effort bzip2 should take before resorting to a slower
fallback compression algorithm.
.Sp
Valid values range from 0 to 250, where 0 means use the default value 30.
.Sp
This option is only valid if the \f(CW\*(C`Method\*(C'\fR is ZIP_CM_BZIP2. It is ignored
otherwise.
.Sp
The default is 0.
.PP
\fILzma and Xz Compression Options\fR
.IX Subsection "Lzma and Xz Compression Options"
.ie n .IP """Preset => number""" 5
.el .IP "\f(CWPreset => number\fR" 5
.IX Item "Preset => number"
Used to choose the LZMA compression preset.
.Sp
Valid values are 0\-9 and \f(CW\*(C`LZMA_PRESET_DEFAULT\*(C'\fR.
.Sp
0 is the fastest compression with the lowest memory usage and the lowest
compression.
.Sp
9 is the slowest compression with the highest memory usage but with the best
compression.
.Sp
This option is only valid if the \f(CW\*(C`Method\*(C'\fR is ZIP_CM_LZMA. It is ignored
otherwise.
.Sp
Defaults to \f(CW\*(C`LZMA_PRESET_DEFAULT\*(C'\fR (6).
.ie n .IP """Extreme => 0|1""" 5
.el .IP "\f(CWExtreme => 0|1\fR" 5
.IX Item "Extreme => 0|1"
Makes LZMA compression a lot slower, but a small compression gain.
.Sp
This option is only valid if the \f(CW\*(C`Method\*(C'\fR is ZIP_CM_LZMA. It is ignored
otherwise.
.Sp
Defaults to 0.
.PP
\fIOther Options\fR
.IX Subsection "Other Options"
.ie n .IP """Time => $number""" 5
.el .IP "\f(CWTime => $number\fR" 5
.IX Item "Time => $number"
Sets the last modified time field in the zip header to \f(CW$number\fR.
.Sp
This field defaults to the time the \f(CW\*(C`IO::Compress::Zip\*(C'\fR object was created
if this option is not specified and the \f(CW$input\fR parameter is not a
filename.
.ie n .IP """ExtAttr => $attr""" 5
.el .IP "\f(CWExtAttr => $attr\fR" 5
.IX Item "ExtAttr => $attr"
This option controls the "external file attributes" field in the central
header of the zip file. This is a 4 byte field.
.Sp
If you are running a Unix derivative this value defaults to
.Sp
.Vb 1
\&    0100644 << 16
.Ve
.Sp
This should allow read/write access to any files that are extracted from
the zip file/buffer`.
.Sp
For all other systems it defaults to 0.
.ie n .IP """exTime => [$atime, $mtime, $ctime]""" 5
.el .IP "\f(CWexTime => [$atime, $mtime, $ctime]\fR" 5
.IX Item "exTime => [$atime, $mtime, $ctime]"
This option expects an array reference with exactly three elements:
\&\f(CW$atime\fR, \f(CW\*(C`mtime\*(C'\fR and \f(CW$ctime\fR. These correspond to the last access
time, last modification time and creation time respectively.
.Sp
It uses these values to set the extended timestamp field (ID is "UT") in
the local zip header using the three values, \f(CW$atime\fR, \f(CW$mtime\fR, \f(CW$ctime\fR. In
addition it sets the extended timestamp field in the central zip header
using \f(CW$mtime\fR.
.Sp
If any of the three values is \f(CW\*(C`undef\*(C'\fR that time value will not be used.
So, for example, to set only the \f(CW$mtime\fR you would use this
.Sp
.Vb 1
\&    exTime => [undef, $mtime, undef]
.Ve
.Sp
If the \f(CW\*(C`Minimal\*(C'\fR option is set to true, this option will be ignored.
.Sp
By default no extended time field is created.
.ie n .IP """exUnix2 => [$uid, $gid]""" 5
.el .IP "\f(CWexUnix2 => [$uid, $gid]\fR" 5
.IX Item "exUnix2 => [$uid, $gid]"
This option expects an array reference with exactly two elements: \f(CW$uid\fR
and \f(CW$gid\fR. These values correspond to the numeric User ID (UID) and Group ID
(GID) of the owner of the files respectively.
.Sp
When the \f(CW\*(C`exUnix2\*(C'\fR option is present it will trigger the creation of a
Unix2 extra field (ID is "Ux") in the local zip header. This will be populated
with \f(CW$uid\fR and \f(CW$gid\fR. An empty Unix2 extra field will also
be created in the central zip header.
.Sp
Note \- The UID & GID are stored as 16\-bit
integers in the "Ux" field. Use \f(CW\*(C`exUnixN\*(C'\fR if your UID or GID are
32\-bit.
.Sp
If the \f(CW\*(C`Minimal\*(C'\fR option is set to true, this option will be ignored.
.Sp
By default no Unix2 extra field is created.
.ie n .IP """exUnixN => [$uid, $gid]""" 5
.el .IP "\f(CWexUnixN => [$uid, $gid]\fR" 5
.IX Item "exUnixN => [$uid, $gid]"
This option expects an array reference with exactly two elements: \f(CW$uid\fR
and \f(CW$gid\fR. These values correspond to the numeric User ID (UID) and Group ID
(GID) of the owner of the files respectively.
.Sp
When the \f(CW\*(C`exUnixN\*(C'\fR option is present it will trigger the creation of a
UnixN extra field (ID is "ux") in both the local and central zip headers.
This will be populated with \f(CW$uid\fR and \f(CW$gid\fR.
The UID & GID are stored as 32\-bit integers.
.Sp
If the \f(CW\*(C`Minimal\*(C'\fR option is set to true, this option will be ignored.
.Sp
By default no UnixN extra field is created.
.ie n .IP """Comment => $comment""" 5
.el .IP "\f(CWComment => $comment\fR" 5
.IX Item "Comment => $comment"
Stores the contents of \f(CW$comment\fR in the Central File Header of
the zip file.
.Sp
Set the \f(CW\*(C`Efs\*(C'\fR option to true if you want to store a UTF8 comment.
.Sp
By default, no comment field is written to the zip file.
.ie n .IP """ZipComment => $comment""" 5
.el .IP "\f(CWZipComment => $comment\fR" 5
.IX Item "ZipComment => $comment"
Stores the contents of \f(CW$comment\fR in the End of Central Directory record
of the zip file.
.Sp
By default, no comment field is written to the zip file.
.ie n .IP """Method => $method""" 5
.el .IP "\f(CWMethod => $method\fR" 5
.IX Item "Method => $method"
Controls which compression method is used. At present the compression
methods supported are: Store (no compression at all), Deflate,
Bzip2, Zstd, Xz and Lzma.
.Sp
The symbols ZIP_CM_STORE, ZIP_CM_DEFLATE, ZIP_CM_BZIP2, ZIP_CM_ZSTD, ZIP_CM_XZ and ZIP_CM_LZMA
are used to select the compression method.
.Sp
These constants are not imported by \f(CW\*(C`IO::Compress::Zip\*(C'\fR by default.
.Sp
.Vb 3
\&    use IO::Compress::Zip qw(:zip_method);
\&    use IO::Compress::Zip qw(:constants);
\&    use IO::Compress::Zip qw(:all);
.Ve
.Sp
Note that to create Bzip2 content, the module \f(CW\*(C`IO::Compress::Bzip2\*(C'\fR must
be installed. A fatal error will be thrown if you attempt to create Bzip2
content when \f(CW\*(C`IO::Compress::Bzip2\*(C'\fR is not available.
.Sp
Note that to create Lzma content, the module \f(CW\*(C`IO::Compress::Lzma\*(C'\fR must
be installed. A fatal error will be thrown if you attempt to create Lzma
content when \f(CW\*(C`IO::Compress::Lzma\*(C'\fR is not available.
.Sp
Note that to create Xz content, the module \f(CW\*(C`IO::Compress::Xz\*(C'\fR must
be installed. A fatal error will be thrown if you attempt to create Xz
content when \f(CW\*(C`IO::Compress::Xz\*(C'\fR is not available.
.Sp
Note that to create Zstd content, the module \f(CW\*(C`IO::Compress::Zstd\*(C'\fR must
be installed. A fatal error will be thrown if you attempt to create Zstd
content when \f(CW\*(C`IO::Compress::Zstd\*(C'\fR is not available.
.Sp
The default method is ZIP_CM_DEFLATE.
.ie n .IP """TextFlag => 0|1""" 5
.el .IP "\f(CWTextFlag => 0|1\fR" 5
.IX Item "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.
.Sp
In one-shot mode this flag will be set to true if the Perl \f(CW\*(C`\-T\*(C'\fR operator thinks
the file contains text.
.Sp
The default is 0.
.ie n .IP """ExtraFieldLocal => $data""" 5
.el .IP "\f(CWExtraFieldLocal => $data\fR" 5
.IX Item "ExtraFieldLocal => $data"
.PD 0
.ie n .IP """ExtraFieldCentral => $data""" 5
.el .IP "\f(CWExtraFieldCentral => $data\fR" 5
.IX Item "ExtraFieldCentral => $data"
.PD
The \f(CW\*(C`ExtraFieldLocal\*(C'\fR option is used to store additional metadata in the
local header for the zip file/buffer. The \f(CW\*(C`ExtraFieldCentral\*(C'\fR does the
same for the matching central header.
.Sp
An extra field consists of zero or more subfields. Each subfield consists
of a two byte header followed by the subfield data.
.Sp
The list of subfields can be supplied in any of the following formats
.Sp
.Vb 4
\&    ExtraFieldLocal => [$id1, $data1,
\&                        $id2, $data2,
\&                         ...
\&                       ]
\&
\&    ExtraFieldLocal => [ [$id1 => $data1],
\&                         [$id2 => $data2],
\&                         ...
\&                       ]
\&
\&    ExtraFieldLocal => { $id1 => $data1,
\&                         $id2 => $data2,
\&                         ...
\&                       }
.Ve
.Sp
Where \f(CW$id1\fR, \f(CW$id2\fR are two byte subfield ID's.
.Sp
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.
.Sp
Alternatively the list of subfields can by supplied as a scalar, thus
.Sp
.Vb 1
\&    ExtraField => $rawdata
.Ve
.Sp
In this case \f(CW\*(C`IO::Compress::Zip\*(C'\fR will check that \f(CW$rawdata\fR consists of
zero or more conformant sub-fields.
.Sp
The Extended Time field (ID "UT"), set using the \f(CW\*(C`exTime\*(C'\fR option, and the
Unix2 extra field (ID "Ux), set using the \f(CW\*(C`exUnix2\*(C'\fR option, are examples
of extra fields.
.Sp
If the \f(CW\*(C`Minimal\*(C'\fR option is set to true, this option will be ignored.
.Sp
The maximum size of an extra field 65535 bytes.
.ie n .IP """Strict => 0|1""" 5
.el .IP "\f(CWStrict => 0|1\fR" 5
.IX Item "Strict => 0|1"
This is a placeholder option.
.SS Examples
.IX Subsection "Examples"
TODO
.SH Methods
.IX Header "Methods"
.SS print
.IX Subsection "print"
Usage is
.PP
.Vb 2
\&    $z\->print($data)
\&    print $z $data
.Ve
.PP
Compresses and outputs the contents of the \f(CW$data\fR parameter. This
has the same behaviour as the \f(CW\*(C`print\*(C'\fR built-in.
.PP
Returns true if successful.
.SS printf
.IX Subsection "printf"
Usage is
.PP
.Vb 2
\&    $z\->printf($format, $data)
\&    printf $z $format, $data
.Ve
.PP
Compresses and outputs the contents of the \f(CW$data\fR parameter.
.PP
Returns true if successful.
.SS syswrite
.IX Subsection "syswrite"
Usage is
.PP
.Vb 3
\&    $z\->syswrite $data
\&    $z\->syswrite $data, $length
\&    $z\->syswrite $data, $length, $offset
.Ve
.PP
Compresses and outputs the contents of the \f(CW$data\fR parameter.
.PP
Returns the number of uncompressed bytes written, or \f(CW\*(C`undef\*(C'\fR if
unsuccessful.
.SS write
.IX Subsection "write"
Usage is
.PP
.Vb 3
\&    $z\->write $data
\&    $z\->write $data, $length
\&    $z\->write $data, $length, $offset
.Ve
.PP
Compresses and outputs the contents of the \f(CW$data\fR parameter.
.PP
Returns the number of uncompressed bytes written, or \f(CW\*(C`undef\*(C'\fR if
unsuccessful.
.SS flush
.IX Subsection "flush"
Usage is
.PP
.Vb 2
\&    $z\->flush;
\&    $z\->flush($flush_type);
.Ve
.PP
Flushes any pending compressed data to the output file/buffer.
.PP
This method takes an optional parameter, \f(CW$flush_type\fR, that controls
how the flushing will be carried out. By default the \f(CW$flush_type\fR
used is \f(CW\*(C`Z_FINISH\*(C'\fR. Other valid values for \f(CW$flush_type\fR are
\&\f(CW\*(C`Z_NO_FLUSH\*(C'\fR, \f(CW\*(C`Z_SYNC_FLUSH\*(C'\fR, \f(CW\*(C`Z_FULL_FLUSH\*(C'\fR and \f(CW\*(C`Z_BLOCK\*(C'\fR. It is
strongly recommended that you only set the \f(CW\*(C`flush_type\*(C'\fR parameter if
you fully understand the implications of what it does \- overuse of \f(CW\*(C`flush\*(C'\fR
can seriously degrade the level of compression achieved. See the \f(CW\*(C`zlib\*(C'\fR
documentation for details.
.PP
Returns true on success.
.SS tell
.IX Subsection "tell"
Usage is
.PP
.Vb 2
\&    $z\->tell()
\&    tell $z
.Ve
.PP
Returns the uncompressed file offset.
.SS eof
.IX Subsection "eof"
Usage is
.PP
.Vb 2
\&    $z\->eof();
\&    eof($z);
.Ve
.PP
Returns true if the \f(CW\*(C`close\*(C'\fR method has been called.
.SS seek
.IX Subsection "seek"
.Vb 2
\&    $z\->seek($position, $whence);
\&    seek($z, $position, $whence);
.Ve
.PP
Provides a sub-set of the \f(CW\*(C`seek\*(C'\fR functionality, with the restriction
that it is only legal to seek forward in the output file/buffer.
It is a fatal error to attempt to seek backward.
.PP
Empty parts of the file/buffer will have NULL (0x00) bytes written to them.
.PP
The \f(CW$whence\fR parameter takes one the usual values, namely SEEK_SET,
SEEK_CUR or SEEK_END.
.PP
Returns 1 on success, 0 on failure.
.SS binmode
.IX Subsection "binmode"
Usage is
.PP
.Vb 2
\&    $z\->binmode
\&    binmode $z ;
.Ve
.PP
This is a noop provided for completeness.
.SS opened
.IX Subsection "opened"
.Vb 1
\&    $z\->opened()
.Ve
.PP
Returns true if the object currently refers to a opened file/buffer.
.SS autoflush
.IX Subsection "autoflush"
.Vb 2
\&    my $prev = $z\->autoflush()
\&    my $prev = $z\->autoflush(EXPR)
.Ve
.PP
If the \f(CW$z\fR object is associated with a file or a filehandle, this method
returns the current autoflush setting for the underlying filehandle. If
\&\f(CW\*(C`EXPR\*(C'\fR is present, and is non-zero, it will enable flushing after every
write/print operation.
.PP
If \f(CW$z\fR is associated with a buffer, this method has no effect and always
returns \f(CW\*(C`undef\*(C'\fR.
.PP
\&\fBNote\fR that the special variable \f(CW$|\fR \fBcannot\fR be used to set or
retrieve the autoflush setting.
.SS input_line_number
.IX Subsection "input_line_number"
.Vb 2
\&    $z\->input_line_number()
\&    $z\->input_line_number(EXPR)
.Ve
.PP
This method always returns \f(CW\*(C`undef\*(C'\fR when compressing.
.SS fileno
.IX Subsection "fileno"
.Vb 2
\&    $z\->fileno()
\&    fileno($z)
.Ve
.PP
If the \f(CW$z\fR object is associated with a file or a filehandle, \f(CW\*(C`fileno\*(C'\fR
will return the underlying file descriptor. Once the \f(CW\*(C`close\*(C'\fR method is
called \f(CW\*(C`fileno\*(C'\fR will return \f(CW\*(C`undef\*(C'\fR.
.PP
If the \f(CW$z\fR object is associated with a buffer, this method will return
\&\f(CW\*(C`undef\*(C'\fR.
.SS close
.IX Subsection "close"
.Vb 2
\&    $z\->close() ;
\&    close $z ;
.Ve
.PP
Flushes any pending compressed data and then closes the output file/buffer.
.PP
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 \f(CW\*(C`close\*(C'\fR method will be called automatically, but
not until global destruction of all live objects when the program is
terminating.
.PP
Therefore, if you want your scripts to be able to run on all versions
of Perl, you should call \f(CW\*(C`close\*(C'\fR explicitly and not rely on automatic
closing.
.PP
Returns true on success, otherwise 0.
.PP
If the \f(CW\*(C`AutoClose\*(C'\fR 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.
.SS newStream([OPTS])
.IX Subsection "newStream([OPTS])"
Usage is
.PP
.Vb 1
\&    $z\->newStream( [OPTS] )
.Ve
.PP
Closes the current compressed data stream and starts a new one.
.PP
OPTS consists of any of the options that are available when creating
the \f(CW$z\fR object.
.PP
See the "Constructor Options" section for more details.
.SS deflateParams
.IX Subsection "deflateParams"
Usage is
.PP
.Vb 1
\&    $z\->deflateParams
.Ve
.PP
TODO
.SH Importing
.IX Header "Importing"
A number of symbolic constants are required by some methods in
\&\f(CW\*(C`IO::Compress::Zip\*(C'\fR. None are imported by default.
.IP :all 5
.IX Item ":all"
Imports \f(CW\*(C`zip\*(C'\fR, \f(CW$ZipError\fR and all symbolic
constants that can be used by \f(CW\*(C`IO::Compress::Zip\*(C'\fR. Same as doing this
.Sp
.Vb 1
\&    use IO::Compress::Zip qw(zip $ZipError :constants) ;
.Ve
.IP :constants 5
.IX Item ":constants"
Import all symbolic constants. Same as doing this
.Sp
.Vb 1
\&    use IO::Compress::Zip qw(:flush :level :strategy :zip_method) ;
.Ve
.IP :flush 5
.IX Item ":flush"
These symbolic constants are used by the \f(CW\*(C`flush\*(C'\fR method.
.Sp
.Vb 6
\&    Z_NO_FLUSH
\&    Z_PARTIAL_FLUSH
\&    Z_SYNC_FLUSH
\&    Z_FULL_FLUSH
\&    Z_FINISH
\&    Z_BLOCK
.Ve
.IP :level 5
.IX Item ":level"
These symbolic constants are used by the \f(CW\*(C`Level\*(C'\fR option in the constructor.
.Sp
.Vb 4
\&    Z_NO_COMPRESSION
\&    Z_BEST_SPEED
\&    Z_BEST_COMPRESSION
\&    Z_DEFAULT_COMPRESSION
.Ve
.IP :strategy 5
.IX Item ":strategy"
These symbolic constants are used by the \f(CW\*(C`Strategy\*(C'\fR option in the constructor.
.Sp
.Vb 5
\&    Z_FILTERED
\&    Z_HUFFMAN_ONLY
\&    Z_RLE
\&    Z_FIXED
\&    Z_DEFAULT_STRATEGY
.Ve
.IP :zip_method 5
.IX Item ":zip_method"
These symbolic constants are used by the \f(CW\*(C`Method\*(C'\fR option in the
constructor.
.Sp
.Vb 3
\&    ZIP_CM_STORE
\&    ZIP_CM_DEFLATE
\&    ZIP_CM_BZIP2
.Ve
.SH EXAMPLES
.IX Header "EXAMPLES"
.SS "Apache::GZip Revisited"
.IX Subsection "Apache::GZip Revisited"
See IO::Compress::FAQ
.SS "Working with Net::FTP"
.IX Subsection "Working with Net::FTP"
See IO::Compress::FAQ
.SH SUPPORT
.IX Header "SUPPORT"
General feedback/questions/bug reports should be sent to
<https://github.com/pmqs/IO\-Compress/issues> (preferred) or
<https://rt.cpan.org/Public/Dist/Display.html?Name=IO\-Compress>.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
Compress::Zlib, IO::Compress::Gzip, IO::Uncompress::Gunzip, IO::Compress::Deflate, IO::Uncompress::Inflate, IO::Compress::RawDeflate, IO::Uncompress::RawInflate, IO::Compress::Bzip2, IO::Uncompress::Bunzip2, IO::Compress::Lzma, IO::Uncompress::UnLzma, IO::Compress::Xz, IO::Uncompress::UnXz, IO::Compress::Lzip, IO::Uncompress::UnLzip, IO::Compress::Lzop, IO::Uncompress::UnLzop, IO::Compress::Lzf, IO::Uncompress::UnLzf, IO::Compress::Zstd, IO::Uncompress::UnZstd, IO::Uncompress::AnyInflate, IO::Uncompress::AnyUncompress
.PP
IO::Compress::FAQ
.PP
File::GlobMapper, Archive::Zip,
Archive::Tar,
IO::Zlib
.PP
For RFC 1950, 1951 and 1952 see
<https://datatracker.ietf.org/doc/html/rfc1950>,
<https://datatracker.ietf.org/doc/html/rfc1951> and
<https://datatracker.ietf.org/doc/html/rfc1952>
.PP
The \fIzlib\fR compression library was written by Jean-loup Gailly
\&\f(CW\*(C`gzip@prep.ai.mit.edu\*(C'\fR and Mark Adler \f(CW\*(C`madler@alumni.caltech.edu\*(C'\fR.
.PP
The primary site for the \fIzlib\fR compression library is
<http://www.zlib.org>.
.PP
The primary site for the \fIzlib-ng\fR compression library is
<https://github.com/zlib\-ng/zlib\-ng>.
.PP
The primary site for gzip is <http://www.gzip.org>.
.SH AUTHOR
.IX Header "AUTHOR"
This module was written by Paul Marquess, \f(CW\*(C`pmqs@cpan.org\*(C'\fR.
.SH "MODIFICATION HISTORY"
.IX Header "MODIFICATION HISTORY"
See the Changes file.
.SH "COPYRIGHT AND LICENSE"
.IX Header "COPYRIGHT AND LICENSE"
Copyright (c) 2005\-2023 Paul Marquess. All rights reserved.
.PP
This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.