io::uncompress::unzip.3

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This means that all normal input file operations can be carried out with
\&\f(CW$z\fR.  For example, to read a line from a compressed file/buffer you can
use either of these forms
.PP
.Vb 2
\&    $line = $z\->getline();
\&    $line = <$z>;
.Ve
.PP
The mandatory parameter \f(CW$input\fR is used to determine the source of the
compressed data. This parameter can take one of three forms.
.IP "A filename" 5
.IX Item "A filename"
If the \f(CW$input\fR parameter is a scalar, it is assumed to be a filename. This
file will be opened for reading and the compressed data will be read from it.
.IP "A filehandle" 5
.IX Item "A filehandle"
If the \f(CW$input\fR parameter is a filehandle, the compressed data will be
read from it.
The string '\-' can be used as an alias for standard input.
.IP "A scalar reference" 5
.IX Item "A scalar reference"
If \f(CW$input\fR is a scalar reference, the compressed data will be read from
\&\f(CW$$output\fR.
.Sh "Constructor Options"
.IX Subsection "Constructor Options"
The option names defined below are case insensitive and can be optionally
prefixed by a '\-'.  So all of the following are valid
.PP
.Vb 4
\&    \-AutoClose
\&    \-autoclose
\&    AUTOCLOSE
\&    autoclose
.Ve
.PP
\&\s-1OPTS\s0 is a combination of 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$input\fR parameter is a filehandle. If
specified, and the value is true, it will result in the file being closed once
either the \f(CW\*(C`close\*(C'\fR method is called or the IO::Uncompress::Unzip object is
destroyed.
.Sp
This parameter defaults to 0.
.ie n .IP """MultiStream => 0|1""" 5
.el .IP "\f(CWMultiStream => 0|1\fR" 5
.IX Item "MultiStream => 0|1"
Treats the complete zip file/buffer as a single compressed data
stream. When reading in multi-stream mode each member of the zip
file/buffer will be uncompressed in turn until the end of the file/buffer
is encountered.
.Sp
This parameter defaults to 0.
.ie n .IP """Prime => $string""" 5
.el .IP "\f(CWPrime => $string\fR" 5
.IX Item "Prime => $string"
This option will uncompress the contents of \f(CW$string\fR before processing the
input file/buffer.
.Sp
This option can be useful when the compressed data is embedded in another
file/data structure and it is not possible to work out where the compressed
data begins without having to read the first few bytes. If this is the
case, the uncompression can be \fIprimed\fR with these bytes using this
option.
.ie n .IP """Transparent => 0|1""" 5
.el .IP "\f(CWTransparent => 0|1\fR" 5
.IX Item "Transparent => 0|1"
If this option is set and the input file/buffer is not compressed data,
the module will allow reading of it anyway.
.Sp
In addition, if the input file/buffer does contain compressed data and
there is non-compressed data immediately following it, setting this option
will make this module treat the whole file/bufffer as a single data stream.
.Sp
This option defaults to 1.
.ie n .IP """BlockSize => $num""" 5
.el .IP "\f(CWBlockSize => $num\fR" 5
.IX Item "BlockSize => $num"
When reading the compressed input data, IO::Uncompress::Unzip will read it in
blocks of \f(CW$num\fR bytes.
.Sp
This option defaults to 4096.
.ie n .IP """InputLength => $size""" 5
.el .IP "\f(CWInputLength => $size\fR" 5
.IX Item "InputLength => $size"
When present this option will limit the number of compressed bytes read
from the input file/buffer to \f(CW$size\fR. This option can be used in the
situation where there is useful data directly after the compressed data
stream and you know beforehand the exact length of the compressed data
stream.
.Sp
This option is mostly used when reading from a filehandle, in which case
the file pointer will be left pointing to the first byte directly after the
compressed data stream.
.Sp
This option defaults to off.
.ie n .IP """Append => 0|1""" 5
.el .IP "\f(CWAppend => 0|1\fR" 5
.IX Item "Append => 0|1"
This option controls what the \f(CW\*(C`read\*(C'\fR method does with uncompressed data.
.Sp
If set to 1, all uncompressed data will be appended to the output parameter
of the \f(CW\*(C`read\*(C'\fR method.
.Sp
If set to 0, the contents of the output parameter of the \f(CW\*(C`read\*(C'\fR method
will be overwritten by the uncompressed data.
.Sp
Defaults to 0.
.ie n .IP """Strict => 0|1""" 5
.el .IP "\f(CWStrict => 0|1\fR" 5
.IX Item "Strict => 0|1"
This option controls whether the extra checks defined below are used when
carrying out the decompression. When Strict is on, the extra tests are
carried out, when Strict is off they are not.
.Sp
The default for this option is off.
.Sh "Examples"
.IX Subsection "Examples"
\&\s-1TODO\s0
.SH "Methods"
.IX Header "Methods"
.Sh "read"
.IX Subsection "read"
Usage is
.PP
.Vb 1
\&    $status = $z\->read($buffer)
.Ve
.PP
Reads a block of compressed data (the size the the compressed block is
determined by the \f(CW\*(C`Buffer\*(C'\fR option in the constructor), uncompresses it and
writes any uncompressed data into \f(CW$buffer\fR. If the \f(CW\*(C`Append\*(C'\fR parameter is
set in the constructor, the uncompressed data will be appended to the
\&\f(CW$buffer\fR parameter. Otherwise \f(CW$buffer\fR will be overwritten.
.PP
Returns the number of uncompressed bytes written to \f(CW$buffer\fR, zero if eof
or a negative number on error.
.Sh "read"
.IX Subsection "read"
Usage is
.PP
.Vb 2
\&    $status = $z\->read($buffer, $length)
\&    $status = $z\->read($buffer, $length, $offset)
\&
\&    $status = read($z, $buffer, $length)
\&    $status = read($z, $buffer, $length, $offset)
.Ve
.PP
Attempt to read \f(CW$length\fR bytes of uncompressed data into \f(CW$buffer\fR.
.PP
The main difference between this form of the \f(CW\*(C`read\*(C'\fR method and the
previous one, is that this one will attempt to return \fIexactly\fR \f(CW$length\fR
bytes. The only circumstances that this function will not is if end-of-file
or an \s-1IO\s0 error is encountered.
.PP
Returns the number of uncompressed bytes written to \f(CW$buffer\fR, zero if eof
or a negative number on error.
.Sh "getline"
.IX Subsection "getline"
Usage is
.PP
.Vb 2
\&    $line = $z\->getline()
\&    $line = <$z>
.Ve
.PP
Reads a single line.
.PP
This method fully supports the use of of the variable \f(CW$/\fR (or
\&\f(CW$INPUT_RECORD_SEPARATOR\fR or \f(CW$RS\fR when \f(CW\*(C`English\*(C'\fR is in use) to
determine what constitutes an end of line. Paragraph mode, record mode and
file slurp mode are all supported.
.Sh "getc"
.IX Subsection "getc"
Usage is
.PP
.Vb 1
\&    $char = $z\->getc()
.Ve
.PP
Read a single character.
.Sh "ungetc"
.IX Subsection "ungetc"
Usage is
.PP
.Vb 1
\&    $char = $z\->ungetc($string)
.Ve
.Sh "inflateSync"
.IX Subsection "inflateSync"
Usage is
.PP
.Vb 1
\&    $status = $z\->inflateSync()
.Ve
.PP
\&\s-1TODO\s0
.Sh "getHeaderInfo"
.IX Subsection "getHeaderInfo"
Usage is
.PP
.Vb 2
\&    $hdr  = $z\->getHeaderInfo();
\&    @hdrs = $z\->getHeaderInfo();
.Ve
.PP
This method returns either a hash reference (in scalar context) or a list
or hash references (in array context) that contains information about each
of the header fields in the compressed data stream(s).
.Sh "tell"
.IX Subsection "tell"
Usage is
.PP
.Vb 2
\&    $z\->tell()
\&    tell $z
.Ve
.PP
Returns the uncompressed file offset.
.Sh "eof"
.IX Subsection "eof"
Usage is
.PP
.Vb 2
\&    $z\->eof();
\&    eof($z);
.Ve
.PP
Returns true if the end of the compressed input stream has been reached.
.Sh "seek"
.IX Subsection "seek"
.Vb 2
\&    $z\->seek($position, $whence);
\&    seek($z, $position, $whence);
.Ve
.PP
Provides a sub-set of the \f(CW\*(C`seek\*(C'\fR functionality, with the restriction
that it is only legal to seek forward in the input file/buffer.
It is a fatal error to attempt to seek backward.
.PP
The \f(CW$whence\fR parameter takes one the usual values, namely \s-1SEEK_SET\s0,
\&\s-1SEEK_CUR\s0 or \s-1SEEK_END\s0.
.PP
Returns 1 on success, 0 on failure.
.Sh "binmode"
.IX Subsection "binmode"
Usage is
.PP
.Vb 2
\&    $z\->binmode
\&    binmode $z ;
.Ve
.PP
This is a noop provided for completeness.
.Sh "opened"
.IX Subsection "opened"
.Vb 1
\&    $z\->opened()
.Ve
.PP
Returns true if the object currently refers to a opened file/buffer.
.Sh "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.
.Sh "input_line_number"
.IX Subsection "input_line_number"
.Vb 2
\&    $z\->input_line_number()
\&    $z\->input_line_number(EXPR)
.Ve
.PP
Returns the current uncompressed line number. If \f(CW\*(C`EXPR\*(C'\fR is present it has
the effect of setting the line number. Note that setting the line number
does not change the current position within the file/buffer being read.
.PP
The contents of \f(CW$/\fR are used to to determine what constitutes a line
terminator.
.Sh "fileno"
.IX Subsection "fileno"
.Vb 2
\&    $z\->fileno()
\&    fileno($z)
.Ve
.PP
If the \f(CW$z\fR object is associated with a file or a filehandle, this method
will return the underlying file descriptor.
.PP
If the \f(CW$z\fR object is is associated with a buffer, this method will
return undef.
.Sh "close"
.IX Subsection "close"
.Vb 2
\&    $z\->close() ;
\&    close $z ;
.Ve
.PP
Closes the output file/buffer.
.PP
For most versions of Perl this method will be automatically invoked if
the IO::Uncompress::Unzip 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::Uncompress::Unzip
object was created, and the object is associated with a file, the
underlying file will also be closed.
.Sh "nextStream"
.IX Subsection "nextStream"
Usage is
.PP
.Vb 1
\&    my $status = $z\->nextStream();
.Ve
.PP
Skips to the next compressed data stream in the input file/buffer. If a new
compressed data stream is found, the eof marker will be cleared and \f(CW$.\fR
will be reset to 0.
.PP
Returns 1 if a new stream was found, 0 if none was found, and \-1 if an
error was encountered.
.Sh "trailingData"
.IX Subsection "trailingData"
Usage is
.PP
.Vb 1
\&    my $data = $z\->trailingData();
.Ve
.PP
Returns the data, if any, that is present immediately after the compressed
data stream once uncompression is complete. It only makes sense to call
this method once the end of the compressed data stream has been
encountered.
.PP
This option can be used when there is useful information immediately
following the compressed data stream, and you don't know the length of the
compressed data stream.
.PP
If the input is a buffer, \f(CW\*(C`trailingData\*(C'\fR will return everything from the
end of the compressed data stream to the end of the buffer.
.PP
If the input is a filehandle, \f(CW\*(C`trailingData\*(C'\fR will return the data that is
left in the filehandle input buffer once the end of the compressed data
stream has been reached. You can then use the filehandle to read the rest
of the input file.
.PP
Don't bother using \f(CW\*(C`trailingData\*(C'\fR if the input is a filename.
.PP
If you know the length of the compressed data stream before you start
uncompressing, you can avoid having to use \f(CW\*(C`trailingData\*(C'\fR by setting the
\&\f(CW\*(C`InputLength\*(C'\fR option in the constructor.
.SH "Importing"
.IX Header "Importing"
No symbolic constants are required by this IO::Uncompress::Unzip at present.
.IP ":all" 5
.IX Item ":all"
Imports \f(CW\*(C`unzip\*(C'\fR and \f(CW$UnzipError\fR.
Same as doing this
.Sp
.Vb 1
\&    use IO::Uncompress::Unzip qw(unzip $UnzipError) ;
.Ve
.SH "EXAMPLES"
.IX Header "EXAMPLES"
.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::Lzop, IO::Uncompress::UnLzop, IO::Compress::Lzf, IO::Uncompress::UnLzf, IO::Uncompress::AnyInflate, IO::Uncompress::AnyUncompress
.PP
Compress::Zlib::FAQ
.PP
File::GlobMapper, Archive::Zip,
Archive::Tar,
IO::Zlib
.PP
For \s-1RFC\s0 1950, 1951 and 1952 see 
\&\fIhttp://www.faqs.org/rfcs/rfc1950.html\fR,
\&\fIhttp://www.faqs.org/rfcs/rfc1951.html\fR and
\&\fIhttp://www.faqs.org/rfcs/rfc1952.html\fR
.PP
The \fIzlib\fR compression library was written by Jean-loup Gailly
\&\[e-mail]\fR and Mark Adler \[e-mail]\fR.
.PP
The primary site for the \fIzlib\fR compression library is
\&\fIhttp://www.zlib.org\fR.
.PP
The primary site for gzip is \fIhttp://www.gzip.org\fR.
.SH "AUTHOR"
.IX Header "AUTHOR"
This module was written by Paul Marquess, \[e-mail]\fR.
.SH "MODIFICATION HISTORY"
.IX Header "MODIFICATION HISTORY"
See the Changes file.
.SH "COPYRIGHT AND LICENSE"
.IX Header "COPYRIGHT AND LICENSE"
Copyright (c) 2005\-2007 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.