zlib Multiple files in one archive

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April 9th, 2003, 09:26 AM

mickro

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zlib Multiple files in one archive

Hi All,

Is it possible to Zip up more than one file into a single .gz file using zlib?

I have been trying the following code which does not seem to work:

PHP Code:


		
			
function compress($filename,$filename2) {        

    $fp = fopen($filename,"rb");

    $data = fread($fp,filesize($filename));

    fclose($fp);



    $fb = fopen($filename2,"rb");

    $data2 = fread($fb,filesize($filename2));

    fclose($fb);

    

    $fd = fopen("$filename.gz","ab");

    $gzdata = gzencode($data,4);

    $gzdata2 = gzencode($data2,4);

    fwrite($fd,$gzdata);

    fwrite($fd,$gzdata2);

    fclose($fd);

    return "$filename.gz";

}

Any ideas would be much appreciated

Cheers

Mike

August 19th, 2003, 07:54 PM

dreamchimney

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any luck ?

im trying the same thing! did you solve this problem?

im using gzwrite instead of gzencode

August 20th, 2003, 05:18 AM

mickro

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Hi dreamchimney,

I found a class which does it well (see attached). Usage is by the following code:

PHP Code:


		
			
<?    

    require("includes/zip.lib.php");    

    if (isset($_POST['action'])) {

        $name = str_replace(" ","_",$_POST["name"]); // replace spaces in filename otherwise won't work

        $cvfile = "cvtemp/$name/cv_" . str_replace(" ","_",$resume_name);

        $letterfile = "cvtemp/$name/letter_" . str_replace(" ","_",$letter_name);

        mkdir("cvtemp/" . $name); // create temporary folder to hold files to be zipped

        copy($resume,$cvfile); // copy posted cv file to temp folder

        copy($letter,$letterfile); // copy posted letter file to temp folder

        $z = new PHPZip();

        $z -> Zip("cvtemp/$name", "zip/$name.zip"); // zip up contents of temp file

        rmdir("cvtemp/$name"); // remove temp file

    }

?>



<form name="upload" action="<?php echo $_SERVER["PHP_SELF"]; ?>" method="post" enctype="multipart/form-data">

<table cellpadding=0 cellspacing=0 summary="upload table">

    <tr>

          <td>Name:</td>

          <td><input name="name" size="30" maxlength="60"></td>

    </tr>

    <tr>

          <td>E-mail:</td>

          <td><input name="email" size="30" maxlength="60"></td>

    </tr>

    <tr>

          <td>Resume:</td>

          <td><input type="file" name="resume"></td>

    </tr>

    <tr>

          <td>Cover Letter:</td>

          <td><input type="file" name="letter"></td>

    </tr>

    <tr>

          <td colspan="2" align="right"><input type="submit" class="submit" name="action" value="Send"></td>

    </tr>

</table>

</form>

You will need to alter the code to meet your specific needs but this should get you going.

HTH

Mike
Digital Egg Ltd

Attached Files

zip.lib.php (7.1 KB, 593 views)

December 11th, 2003, 02:05 PM

jbuckle24

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hello,

just wondering where you found the file you attached? Was there any more documentation than what was provided? This will be very helpful, but I was wondering if their was a way to unzip the folder aftwerwards?

thanks,
-jbuckle24

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December 11th, 2003, 02:35 PM

realnowhereman

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Folks, fyi ...

A gzipped file contains exactly one file. The usual way to use gzip compression on several files is to put them into a tar archive, which can be done using Archive_Tar ( http://www.devshed.com/Server_Side/...File/page1.html) and to compress the tar file.

HTH

December 12th, 2003, 01:15 PM

holroy

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Quote:

Originally posted by realnowhereman
Folks, fyi ...

A gzipped file contains exactly one file. The usual way to use gzip compression on several files is to put them into a tar archive, which can be done using Archive_Tar ( http://www.devshed.com/Server_Side/...File/page1.html) and to compress the tar file.

HTH

Not necessarily correct! Look at http://www.ietf.org/rfc/rfc1952.txt . This clearly states in section 2.2 on file formats:

Quote:

2.2. File format

A gzip file consists of a series of "members" (compressed data sets). The format of each member is specified in the following section. The members simply appear one after another in the file, with no additional information before, between, or after them.

Albeit I'll agree that the usual way is to do the tar first, and then gzip the result. And this does also provide proper handling of filenames and directories and stuff.

As for alternatives, it's not so hard to produce a proper zip file, either using the zlib or (gzip on unix when no zlib available), and neither to process this zipped file. For starters on the format to use, see http://www.pkware.com/products/ente...ers/appnote.txt

I've build my own zip/unzip classes already, but they only uses in-memory files, and are not for public view. At least not yet, but I'm seriously thinking of producing zip/unzip classes loosely build on top of zlib. Time will show if I will publish these scripts/classes or not.

But back to the original problem, if adding several members (that is several gzdeflated files) into one file, then you need a proper tool to decompress them, and I'm not sure how zlib handles that. But it's possible, so keep trying.

<e><

December 12th, 2003, 02:08 PM

realnowhereman

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You're right, several files are possible. However, gzip considers several members in an archive to be concatenated data. Do other programmes handle that differently?

Thanks for the links.

December 14th, 2003, 09:28 AM

holroy

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I've not studied very well which programs does what, but I know that within the header of each member there are (optional) fields to tell the filename. But I don't know which programs (if any/all) sets this filename, and I don't know how cares when reading the file.

As such, it is much wiser to use the tar.gz-format which is publicly known mainly within the unix community, but at a steadily higher degree in Windows as weel (through the use of WinZip, at least). Or to use the PK Zip-file format, which is understood on both platforms.

Sorry for not including references to Mac here, but I haven't used that to any extent, but I have a faint idea that the PK Zip-file format is a little more known than tar.gz. What (I think) I do know is that the Mac format of .sit or .hqx(?) are not that widely supported the other way around. (Although WinZip gets most of what you throw at it... )

<e><