io::uncompress::anyinflate.3

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concatenation of all the uncompressed data from each of the input
files/buffers.
.Sh "Optional Parameters"
.IX Subsection "Optional Parameters"
Unless specified below, the optional parameters for \f(CW\*(C`anyinflate\*(C'\fR,
\&\f(CW\*(C`OPTS\*(C'\fR, are the same as those used with the \s-1OO\s0 interface defined in the
\&\*(L"Constructor Options\*(R" section 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`anyinflate\*(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`anyinflate\*(C'\fR has
completed.
.Sp
This parameter defaults to 0.
.ie n .IP """BinModeOut => 0|1""" 5
.el .IP "\f(CWBinModeOut => 0|1\fR" 5
.IX Item "BinModeOut => 0|1"
When writing to a file or filehandle, set \f(CW\*(C`binmode\*(C'\fR before writing to the
file.
.Sp
Defaults to 0.
.ie n .IP """Append => 0|1""" 5
.el .IP "\f(CWAppend => 0|1\fR" 5
.IX Item "Append => 0|1"
\&\s-1TODO\s0
.ie n .IP """MultiStream => 0|1""" 5
.el .IP "\f(CWMultiStream => 0|1\fR" 5
.IX Item "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.
.Sp
Defaults to 0.
.ie n .IP """TrailingData => $scalar""" 5
.el .IP "\f(CWTrailingData => $scalar\fR" 5
.IX Item "TrailingData => $scalar"
Returns the data, if any, that is present immediately after the compressed
data stream once uncompression is complete.
.Sp
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.
.Sp
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.
.Sp
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.
.Sp
Don't bother using \f(CW\*(C`trailingData\*(C'\fR if the input is a filename.
.Sp
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.
.Sh "Examples"
.IX Subsection "Examples"
To read the contents of the file \f(CW\*(C`file1.txt.Compressed\*(C'\fR and write the
compressed data to the file \f(CW\*(C`file1.txt\*(C'\fR.
.PP
.Vb 3
\&    use strict ;
\&    use warnings ;
\&    use IO::Uncompress::AnyInflate qw(anyinflate $AnyInflateError) ;
\&
\&    my $input = "file1.txt.Compressed";
\&    my $output = "file1.txt";
\&    anyinflate $input => $output
\&        or die "anyinflate failed: $AnyInflateError\en";
.Ve
.PP
To read from an existing Perl filehandle, \f(CW$input\fR, and write the
uncompressed data to a buffer, \f(CW$buffer\fR.
.PP
.Vb 4
\&    use strict ;
\&    use warnings ;
\&    use IO::Uncompress::AnyInflate qw(anyinflate $AnyInflateError) ;
\&    use IO::File ;
\&
\&    my $input = new IO::File "<file1.txt.Compressed"
\&        or die "Cannot open \*(Aqfile1.txt.Compressed\*(Aq: $!\en" ;
\&    my $buffer ;
\&    anyinflate $input => \e$buffer 
\&        or die "anyinflate failed: $AnyInflateError\en";
.Ve
.PP
To uncompress all files in the directory \*(L"/my/home\*(R" that match \*(L"*.txt.Compressed\*(R" and store the compressed data in the same directory
.PP
.Vb 3
\&    use strict ;
\&    use warnings ;
\&    use IO::Uncompress::AnyInflate qw(anyinflate $AnyInflateError) ;
\&
\&    anyinflate \*(Aq</my/home/*.txt.Compressed>\*(Aq => \*(Aq</my/home/#1.txt>\*(Aq
\&        or die "anyinflate failed: $AnyInflateError\en";
.Ve
.PP
and if you want to compress each file one at a time, this will do the trick
.PP
.Vb 3
\&    use strict ;
\&    use warnings ;
\&    use IO::Uncompress::AnyInflate qw(anyinflate $AnyInflateError) ;
\&
\&    for my $input ( glob "/my/home/*.txt.Compressed" )
\&    {
\&        my $output = $input;
\&        $output =~ s/.Compressed// ;
\&        anyinflate $input => $output 
\&            or die "Error compressing \*(Aq$input\*(Aq: $AnyInflateError\en";
\&    }
.Ve
.SH "OO Interface"
.IX Header "OO Interface"
.Sh "Constructor"
.IX Subsection "Constructor"
The format of the constructor for IO::Uncompress::AnyInflate is shown below
.PP
.Vb 2
\&    my $z = new IO::Uncompress::AnyInflate $input [OPTS]
\&        or die "IO::Uncompress::AnyInflate failed: $AnyInflateError\en";
.Ve
.PP
Returns an \f(CW\*(C`IO::Uncompress::AnyInflate\*(C'\fR object on success and undef on failure.
The variable \f(CW$AnyInflateError\fR will contain an error message on failure.
.PP
If you are running Perl 5.005 or better the object, \f(CW$z\fR, returned from
IO::Uncompress::AnyInflate can be used exactly like an IO::File filehandle.
This means that all normal input file operations can be carried out with
\&\f(CW$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::AnyInflate 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"
Allows multiple concatenated compressed streams to be treated as a single
compressed stream. Decompression will stop once either the end of the
file/buffer is reached, an error is encountered (premature eof, corrupt
compressed data) or the end of a stream is not immediately followed by the
start of another stream.
.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 => $num"
When reading the compressed input data, IO::Uncompress::AnyInflate will read it in
blocks of \f(CW$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.
.Sp
If the input is an \s-1RFC\s0 1950 data stream, the following will be checked:
.RS 5
.IP "1." 5
The \s-1ADLER32\s0 checksum field must be present.
.IP "2." 5
The value of the \s-1ADLER32\s0 field read must match the adler32 value of the
uncompressed data actually contained in the file.
.RE
.RS 5
.Sp
If the input is a gzip (\s-1RFC\s0 1952) data stream, the following will be checked:
.IP "1." 5
If the \s-1FHCRC\s0 bit is set in the gzip \s-1FLG\s0 header byte, the \s-1CRC16\s0 bytes in the
header must match the crc16 value of the gzip header actually read.
.IP "2." 5
If the gzip header contains a name field (\s-1FNAME\s0) it consists solely of \s-1ISO\s0
8859\-1 characters.
.IP "3." 5
If the gzip header contains a comment field (\s-1FCOMMENT\s0) it consists solely
of \s-1ISO\s0 8859\-1 characters plus line-feed.
.IP "4." 5
If the gzip \s-1FEXTRA\s0 header field is present it must conform to the sub-field
structure as defined in \s-1RFC\s0 1952.
.IP "5." 5
The \s-1CRC32\s0 and \s-1ISIZE\s0 trailer fields must be present.
.IP "6." 5
The value of the \s-1CRC32\s0 field read must match the crc32 value of the
uncompressed data actually contained in the gzip file.
.IP "7." 5
The value of the \s-1ISIZE\s0 fields read must match the length of the
uncompressed data actually read from the file.
.RE
.RS 5
.RE
.ie n .IP """RawInflate => 0|1""" 5
.el .IP "\f(CWRawInflate => 0|1\fR" 5
.IX Item "RawInflate => 0|1"
When auto-detecting the compressed format, try to test for raw-deflate (\s-1RFC\s0
1951) content using the \f(CW\*(C`IO::Uncompress::RawInflate\*(C'\fR module.
.Sp
The reason this is not default behaviour is because \s-1RFC\s0 1951 content can
only be detected by attempting to uncompress it. This process is error
prone and can result is false positives.
.Sp
Defaults to 0.
.ie n .IP """ParseExtra => 0|1"" If the gzip \s-1FEXTRA\s0 header field is present and this option is set, it will force the module to check that it conforms to the sub-field structure as defined in \s-1RFC\s0 1952." 5
.el .IP "\f(CWParseExtra => 0|1\fR If the gzip \s-1FEXTRA\s0 header field is present and this option is set, it will force the module to check that it conforms to the sub-field structure as defined in \s-1RFC\s0 1952." 5
.IX Item "ParseExtra => 0|1 If the gzip FEXTRA header field is present and this option is set, it will force the module to check that it conforms to the sub-field structure as defined in RFC 1952."
If the \f(CW\*(C`Strict\*(C'\fR is on it will automatically enable this option.
.Sp
Defaults to 0.
.Sh "Examples"
.IX Subsection "Examples"