PHP 5.6.0beta1 released

gzwrite

(PHP 4, PHP 5)

gzwriteAusgabe in gz-komprimierte Dateien

Beschreibung

int gzwrite ( resource $zp , string $string [, int $length ] )

gzwrite() schreibt den Inhalt von string in die angegebene gz-Datei aus.

Parameter-Liste

zp

Eine gz-Datei Resource. Diese muss gültig sein und auf eine Datei zeigen die erfolgreich mit gzopen() geöffnet wurde.

string

Der auszugebende String.

length

Die Anzahl unkomprimierter Bytes die ausgegeben werden soll. Wenn angegeben wird nach length geschriebenen Bytes aus string abgebrochen wenn bis dahin das Ende des Strings nicht erreicht ist.

Hinweis:

Beachten Sie das der magic_quotes_runtime Konfigurationsparameter ignoriert wird und keine Slashes aus string entfernt werden wenn der optionale Parameter length übergeben wird.

Rückgabewerte

Gibt die Anzahl der (unkomprimierten) Bytes zurück die auf den gegebenen gz-Stream ausgegeben wurden.

Beispiele

Beispiel #1 gzwrite() Beispiel

<?php
$string 
'Zu komprimierende Daten';
$gz gzopen('somefile.gz','w9');
gzwrite($gz$string);
gzclose($gz);
?>

Siehe auch

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User Contributed Notes 6 notes

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2
Kioob
10 years ago
This is a short example of use gzwrite function.
<?php
function gzcompressfile($source,$level=false){
   
$dest=$source.'.gz';
   
$mode='wb'.$level;
   
$error=false;
    if(
$fp_out=gzopen($dest,$mode)){
        if(
$fp_in=fopen($source,'rb')){
            while(!
feof($fp_in))
               
gzwrite($fp_out,fread($fp_in,1024*512));
           
fclose($fp_in);
            }
          else
$error=true;
       
gzclose($fp_out);
        }
      else
$error=true;
    if(
$error) return false;
      else return
$dest;
    }
?>

the function gzcompressfile() compress a file 'data.csv' to 'data.csv.gz'. the function return false if error, and the new file name if it's ok.
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0
Take Heed
3 years ago
Read the description of gzwrite() very carefully.  If the 'length' option is not specified, then the input data will have slashes stripped on systems where magic quotes are enabled.  This is important information to know when compressing files.

<?php
$data
= fread($fp, 5000);
gzwrite($fp2, $data, strlen($data));
?>

Is the correct way to avoid issues with magic quotes.
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0
calmarius at nospam dot atw dot hu
5 years ago
gz compression is often used with tar archives. Building tar archives is quite easy. Here is a code snipplet which can be used for building tar archives before compressing them to tar.gz.

<?php

//\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
// Adds file header to the tar file, it is used before adding file content.
// f: file resource (provided by eg. fopen)
// phisfn: path to file
// archfn: path to file in archive, directory names must be followed by '/'
//\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
function TarAddHeader($f,$phisfn,$archfn)
{
   
$info=stat($phisfn);
   
$ouid=sprintf("%6s ", decoct($info[4]));
   
$ogid=sprintf("%6s ", decoct($info[5]));
   
$omode=sprintf("%6s ", decoct(fileperms($phisfn)));
   
$omtime=sprintf("%11s", decoct(filemtime($phisfn)));
    if (@
is_dir($phisfn))
    {
        
$type="5";
        
$osize=sprintf("%11s ", decoct(0));
    }
    else
    {
        
$type='';
        
$osize=sprintf("%11s ", decoct(filesize($phisfn)));
        
clearstatcache();
    }
   
$dmajor = '';
   
$dminor = '';
   
$gname = '';
   
$linkname = '';
   
$magic = '';
   
$prefix = '';
   
$uname = '';
   
$version = '';
   
$chunkbeforeCS=pack("a100a8a8a8a12A12",$archfn, $omode, $ouid, $ogid, $osize, $omtime);
   
$chunkafterCS=pack("a1a100a6a2a32a32a8a8a155a12", $type, $linkname, $magic, $version, $uname, $gname, $dmajor, $dminor ,$prefix,'');

   
$checksum = 0;
    for (
$i=0; $i<148; $i++) $checksum+=ord(substr($chunkbeforeCS,$i,1));
    for (
$i=148; $i<156; $i++) $checksum+=ord(' ');
    for (
$i=156, $j=0; $i<512; $i++, $j++)    $checksum+=ord(substr($chunkafterCS,$j,1));

   
fwrite($f,$chunkbeforeCS,148);
   
$checksum=sprintf("%6s ",decoct($checksum));
   
$bdchecksum=pack("a8", $checksum);
   
fwrite($f,$bdchecksum,8);
   
fwrite($f,$chunkafterCS,356);
    return
true;
}
//\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/
// Writes file content to the tar file must be called after a TarAddHeader
// f:file resource provided by fopen
// phisfn: path to file
//\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/
function TarWriteContents($f,$phisfn)
{
    if (@
is_dir($phisfn))
    {
        return;
    }
    else
    {
       
$size=filesize($phisfn);
       
$padding=$size % 512 ? 512-$size%512 : 0;
       
$f2=fopen($phisfn,"rb");
        while (!
feof($f2)) fwrite($f,fread($f2,1024*1024));
       
$pstr=sprintf("a%d",$padding);
       
fwrite($f,pack($pstr,''));
    }
}
//\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/
// Adds 1024 byte footer at the end of the tar file
// f: file resource
//\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/
function TarAddFooter($f)
{
   
fwrite($f,pack('a1024',''));
}

?>
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0
repository at lamaresh dot net
5 years ago
This function add a line to a .gz compressed file

<?php
function AppendLineGz($file,$string) {
    if (
file_exists($file)) {
       
$lines = gzfile($file);
       
$lines[count($lines)] = "$string\r\n";
       
$input=implode($lines);
    } else {
$input="$string\r\n";}
   
$gz = gzopen($file,'w9');
   
gzwrite($gz, $input);
   
gzclose($gz);   
}
?>
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0
Anonymous
6 years ago
katzlbtjunk's method is certainly shorter, but it is unusable for anything except small files.  It would try to load the whole file into memory, then create an entire compressed copy, and only then write it to disk.  The other method given below will not exhaust memory like that.
up
-1
katzlbtjunk at hotmail dot com
6 years ago
How about this instead:
$s = file_get_contents('file.tar');
file_put_contents('file.tar.gz',gzencode($s,9));
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