Zlib(3)

NAME
IO::Zlib - IO:: style interface to Compress::Zlib

SYNOPSIS
With any version of Perl 5 you can use the basic OO interface:

    use IO::Zlib;

    $fh = new IO::Zlib;
    if ($fh->open("file.gz", "rb")) {
        print <$fh>;
        $fh->close;
    }

    $fh = IO::Zlib->new("file.gz", "wb9");
    if (defined $fh) {
        print $fh "bar\n";
        $fh->close;
    }

    $fh = IO::Zlib->new("file.gz", "rb");
    if (defined $fh) {
        print <$fh>;
        undef $fh;       # automatically closes the file
    }

With Perl 5.004 you can also use the TIEHANDLE interface to access compressed files just like ordinary files:

    use IO::Zlib;

    tie *FILE, 'IO::Zlib', "file.gz", "wb";
    print FILE "line 1\nline2\n";

    tie *FILE, 'IO::Zlib', "file.gz", "rb";
    while (<FILE>) { print "LINE: ", $_ };

DESCRIPTION
"IO::Zlib" provides an IO:: style interface to Compress::Zlib and hence to gzip/zlib compressed files. It provides many of the same methods as the IO::Handle interface.

CONSTRUCTOR

new ( [ARGS] )
    Creates an "IO::Zlib" object. If it receives any parameters, they are passed to the method "open"; if the open fails, the object is destroyed. Otherwise, it is returned to the caller.

METHODS

open ( FILENAME, MODE )
    "open" takes two arguments. The first is the name of the file to open and the second is the open mode. The mode can be anything acceptable to Compress::Zlib and by extension anything acceptable to zlib (that basically means POSIX fopen() style mode strings plus an optional number to indicate the compression level).

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

close
    Close the file associated with the object and disassociate the file from the handle. Done automatically on destroy.

getc
    Return the next character from the file, or undef if none remain.

getline
    Return the next line from the file, or undef on end of string. Can safely be called in an array context. Currently ignores $/ ($INPUT_RECORD_SEPARATOR or $RS when English is in use) and treats lines as delimited by "\n".

getlines
    Get all remaining lines from the file. It will croak() if accidentally called in a scalar context.

print ( ARGS... )
    Print ARGS to the file.

read ( BUF, NBYTES, [OFFSET] )
    Read some bytes from the file. Returns the number of bytes actually read, 0 on end-of-file, undef on error.

eof Returns true if the handle is currently positioned at end of file?

seek ( OFFSET, WHENCE )
    Seek to a given position in the stream. Not yet supported.

tell
    Return the current position in the stream, as a numeric offset. Not yet supported.

setpos ( POS )
    Set the current position, using the opaque value returned by "getpos()". Not yet supported.

getpos ( POS )
    Return the current position in the string, as an opaque object. Not yet supported.

SEE ALSO
perlfunc, "I/O Operators" in perlop, IO::Handle, Compress::Zlib

HISTORY
Created by Tom Hughes <tom@compton.nu>.

COPYRIGHT
Copyright (c) 1998-2001 Tom Hughes <tom@compton.nu>. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.