IO::Uncompress::Unzip - Read zip files/buffers
use IO::Uncompress::Unzip qw(unzip $UnzipError) ; my $status = unzip $input => $output [,OPTS] or die "unzip failed: $UnzipError\n"; my $z = new IO::Uncompress::Unzip $input [OPTS] or die "unzip failed: $UnzipError\n"; $status = $z->read($buffer) $status = $z->read($buffer, $length) $status = $z->read($buffer, $length, $offset) $line = $z->getline() $char = $z->getc() $char = $z->ungetc() $char = $z->opened() $status = $z->inflateSync() $data = $z->trailingData() $status = $z->nextStream() $data = $z->getHeaderInfo() $z->tell() $z->seek($position, $whence) $z->binmode() $z->fileno() $z->eof() $z->close() $UnzipError ; # IO::File mode <$z> read($z, $buffer); read($z, $buffer, $length); read($z, $buffer, $length, $offset); tell($z) seek($z, $position, $whence) binmode($z) fileno($z) eof($z) close($z)
This module provides a Perl interface that allows the reading of zlib files/buffers.
For writing zip files/buffers, see the companion module IO::Compress::Zip.
A top-level function, unzip, is provided to carry out "one-shot" uncompression between buffers and/or files. For finer control over the uncompression process, see the "OO Interface" section.
unzip
use IO::Uncompress::Unzip qw(unzip $UnzipError) ; unzip $input => $output [,OPTS] or die "unzip failed: $UnzipError\n";
The functional interface needs Perl5.005 or better.
unzip expects at least two parameters, $input and $output.
$input
$output
The parameter, $input, is used to define the source of the compressed data.
It can take one of the following forms:
If the $input 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.
If the $input parameter is a filehandle, the input data will be read from it. The string '-' can be used as an alias for standard input.
If $input is a scalar reference, the input data will be read from $$input.
$$input
If $input is an array reference, each element in the array must be a filename.
The input data will be read from each file in turn.
The complete array will be walked to ensure that it only contains valid filenames before any data is uncompressed.
If $input is a string that is delimited by the characters "<" and ">" unzip will assume that it is an input fileglob string. The input is the list of files that match the fileglob.
If the fileglob does not match any files ...
See File::GlobMapper for more details.
If the $input parameter is any other type, undef will be returned.
undef
The parameter $output is used to control the destination of the uncompressed data. This parameter can take one of these forms.
If the $output parameter is a simple scalar, it is assumed to be a filename. This file will be opened for writing and the uncompressed data will be written to it.
If the $output parameter is a filehandle, the uncompressed data will be written to it. The string '-' can be used as an alias for standard output.
If $output is a scalar reference, the uncompressed data will be stored in $$output.
$$output
If $output is an array reference, the uncompressed data will be pushed onto the array.
If $output is a string that is delimited by the characters "<" and ">" unzip will assume that it is an output fileglob string. The output is the list of files that match the fileglob.
When $output is an fileglob string, $input must also be a fileglob string. Anything else is an error.
If the $output parameter is any other type, undef will be returned.
When $input maps to multiple compressed files/buffers and $output is a single file/buffer, after uncompression $output will contain a concatenation of all the uncompressed data from each of the input files/buffers.
Unless specified below, the optional parameters for unzip, OPTS, are the same as those used with the OO interface defined in the "Constructor Options" section below.
OPTS
AutoClose => 0|1
This option applies to any input or output data streams to unzip that are filehandles.
If AutoClose is specified, and the value is true, it will result in all input and/or output filehandles being closed once unzip has completed.
AutoClose
This parameter defaults to 0.
BinModeOut => 0|1
When writing to a file or filehandle, set binmode before writing to the file.
binmode
Defaults to 0.
Append => 0|1
TODO
MultiStream => 0|1
If the input file/buffer contains multiple compressed data streams, this option will uncompress the whole lot as a single data stream.
TrailingData => $scalar
Returns the data, if any, that is present immediately after the compressed data stream once uncompression is complete.
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.
If the input is a buffer, trailingData will return everything from the end of the compressed data stream to the end of the buffer.
trailingData
If the input is a filehandle, trailingData 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.
Don't bother using trailingData if the input is a filename.
If you know the length of the compressed data stream before you start uncompressing, you can avoid having to use trailingData by setting the InputLength option.
InputLength
To read the contents of the file file1.txt.zip and write the compressed data to the file file1.txt.
file1.txt.zip
file1.txt
use strict ; use warnings ; use IO::Uncompress::Unzip qw(unzip $UnzipError) ; my $input = "file1.txt.zip"; my $output = "file1.txt"; unzip $input => $output or die "unzip failed: $UnzipError\n";
To read from an existing Perl filehandle, $input, and write the uncompressed data to a buffer, $buffer.
$buffer
use strict ; use warnings ; use IO::Uncompress::Unzip qw(unzip $UnzipError) ; use IO::File ; my $input = new IO::File "<file1.txt.zip" or die "Cannot open 'file1.txt.zip': $!\n" ; my $buffer ; unzip $input => \$buffer or die "unzip failed: $UnzipError\n";
To uncompress all files in the directory "/my/home" that match "*.txt.zip" and store the compressed data in the same directory
use strict ; use warnings ; use IO::Uncompress::Unzip qw(unzip $UnzipError) ; unzip '</my/home/*.txt.zip>' => '</my/home/#1.txt>' or die "unzip failed: $UnzipError\n";
and if you want to compress each file one at a time, this will do the trick
use strict ; use warnings ; use IO::Uncompress::Unzip qw(unzip $UnzipError) ; for my $input ( glob "/my/home/*.txt.zip" ) { my $output = $input; $output =~ s/.zip// ; unzip $input => $output or die "Error compressing '$input': $UnzipError\n"; }
The format of the constructor for IO::Uncompress::Unzip is shown below
my $z = new IO::Uncompress::Unzip $input [OPTS] or die "IO::Uncompress::Unzip failed: $UnzipError\n";
Returns an IO::Uncompress::Unzip object on success and undef on failure. The variable $UnzipError will contain an error message on failure.
IO::Uncompress::Unzip
$UnzipError
If you are running Perl 5.005 or better the object, $z, returned from IO::Uncompress::Unzip can be used exactly like an IO::File filehandle. This means that all normal input file operations can be carried out with $z. For example, to read a line from a compressed file/buffer you can use either of these forms
$z
$line = $z->getline(); $line = <$z>;
The mandatory parameter $input is used to determine the source of the compressed data. This parameter can take one of three forms.
If the $input 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.
If the $input parameter is a filehandle, the compressed data will be read from it. The string '-' can be used as an alias for standard input.
If $input is a scalar reference, the compressed data will be read from $$output.
The option names defined below are case insensitive and can be optionally prefixed by a '-'. So all of the following are valid
-AutoClose -autoclose AUTOCLOSE autoclose
OPTS is a combination of the following options:
This option is only valid when the $input parameter is a filehandle. If specified, and the value is true, it will result in the file being closed once either the close method is called or the IO::Uncompress::Unzip object is destroyed.
close
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.
Prime => $string
This option will uncompress the contents of $string before processing the input file/buffer.
$string
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 primed with these bytes using this option.
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.
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.
This option defaults to 1.
BlockSize => $num
When reading the compressed input data, IO::Uncompress::Unzip will read it in blocks of $num bytes.
$num
This option defaults to 4096.
InputLength => $size
When present this option will limit the number of compressed bytes read from the input file/buffer to $size. 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.
$size
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.
This option defaults to off.
This option controls what the read method does with uncompressed data.
read
If set to 1, all uncompressed data will be appended to the output parameter of the read method.
If set to 0, the contents of the output parameter of the read method will be overwritten by the uncompressed data.
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.
The default for this option is off.
Usage is
$status = $z->read($buffer)
Reads a block of compressed data (the size the the compressed block is determined by the Buffer option in the constructor), uncompresses it and writes any uncompressed data into $buffer. If the Append parameter is set in the constructor, the uncompressed data will be appended to the $buffer parameter. Otherwise $buffer will be overwritten.
Buffer
Append
Returns the number of uncompressed bytes written to $buffer, zero if eof or a negative number on error.
$status = $z->read($buffer, $length) $status = $z->read($buffer, $length, $offset) $status = read($z, $buffer, $length) $status = read($z, $buffer, $length, $offset)
Attempt to read $length bytes of uncompressed data into $buffer.
$length
The main difference between this form of the read method and the previous one, is that this one will attempt to return exactly $length bytes. The only circumstances that this function will not is if end-of-file or an IO error is encountered.
$line = $z->getline() $line = <$z>
Reads a single line.
This method fully supports the use of of the variable $/ (or $INPUT_RECORD_SEPARATOR or $RS when English is in use) to determine what constitutes an end of line. Paragraph mode, record mode and file slurp mode are all supported.
$/
$INPUT_RECORD_SEPARATOR
$RS
English
$char = $z->getc()
Read a single character.
$char = $z->ungetc($string)
$status = $z->inflateSync()
$hdr = $z->getHeaderInfo(); @hdrs = $z->getHeaderInfo();
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).
$z->tell() tell $z
Returns the uncompressed file offset.
$z->eof(); eof($z);
Returns true if the end of the compressed input stream has been reached.
$z->seek($position, $whence); seek($z, $position, $whence);
Provides a sub-set of the seek 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.
seek
The $whence parameter takes one the usual values, namely SEEK_SET, SEEK_CUR or SEEK_END.
$whence
Returns 1 on success, 0 on failure.
$z->binmode binmode $z ;
This is a noop provided for completeness.
$z->opened()
Returns true if the object currently refers to a opened file/buffer.
my $prev = $z->autoflush() my $prev = $z->autoflush(EXPR)
If the $z object is associated with a file or a filehandle, this method returns the current autoflush setting for the underlying filehandle. If EXPR is present, and is non-zero, it will enable flushing after every write/print operation.
EXPR
If $z is associated with a buffer, this method has no effect and always returns undef.
Note that the special variable $| cannot be used to set or retrieve the autoflush setting.
$|
$z->input_line_number() $z->input_line_number(EXPR)
Returns the current uncompressed line number. If EXPR 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.
The contents of $/ are used to to determine what constitutes a line terminator.
$z->fileno() fileno($z)
If the $z object is associated with a file or a filehandle, fileno will return the underlying file descriptor. Once the close method is called fileno will return undef.
fileno
If the $z object is is associated with a buffer, this method will return undef.
$z->close() ; close $z ;
Closes the output file/buffer.
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 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 close explicitly and not rely on automatic closing.
Returns true on success, otherwise 0.
If the AutoClose 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.
my $status = $z->nextStream();
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 $. will be reset to 0.
$.
Returns 1 if a new stream was found, 0 if none was found, and -1 if an error was encountered.
my $data = $z->trailingData();
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.
If you know the length of the compressed data stream before you start uncompressing, you can avoid having to use trailingData by setting the InputLength option in the constructor.
No symbolic constants are required by this IO::Uncompress::Unzip at present.
Imports unzip and $UnzipError. Same as doing this
use IO::Uncompress::Unzip qw(unzip $UnzipError) ;
See IO::Uncompress::Unzip::FAQ
The code below can be used to traverse a zip file, one compressed data stream at a time.
use IO::Uncompress::Unzip qw($UnzipError); my $zipfile = "somefile.zip"; my $u = new IO::Uncompress::Unzip $zipfile or die "Cannot open $zipfile: $UnzipError"; my $status; for ($status = 1; ! $u->eof(); $status = $u->nextStream()) { my $name = $u->getHeaderInfo()->{Name}; warn "Processing member $name\n" ; my $buff; while (($status = $u->read($buff)) > 0) { # Do something here } last unless $status == 0; } die "Error processing $zipfile: $!\n" if $status < 0 ;
Each individual compressed data stream is read until the logical end-of-file is reached. Then nextStream is called. This will skip to the start of the next compressed data stream and clear the end-of-file flag.
nextStream
It is also worth noting that nextStream can be called at any time -- you don't have to wait until you have exhausted a compressed data stream before skipping to the next one.
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
Compress::Zlib::FAQ
File::GlobMapper, Archive::Zip, Archive::Tar, IO::Zlib
For RFC 1950, 1951 and 1952 see http://www.faqs.org/rfcs/rfc1950.html, http://www.faqs.org/rfcs/rfc1951.html and http://www.faqs.org/rfcs/rfc1952.html
The zlib compression library was written by Jean-loup Gailly gzip@prep.ai.mit.edu and Mark Adler madler@alumni.caltech.edu.
The primary site for the zlib compression library is http://www.zlib.org.
The primary site for gzip is http://www.gzip.org.
This module was written by Paul Marquess, pmqs@cpan.org.
See the Changes file.
Copyright (c) 2005-2008 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.
To install MakeUtil, copy and paste the appropriate command in to your terminal.
cpanm
cpanm MakeUtil
CPAN shell
perl -MCPAN -e shell install MakeUtil
For more information on module installation, please visit the detailed CPAN module installation guide.