PHP fopen() memory usage while Merging many files together

Question

I have many file chunks and I need to merge them using PHP fopen function.However, I'm worring about the memory usage. For example,I got about 100 files listed in split_hash.txt,each is about 100mb. And here I combine them together:

<?php  
$hash = file_get_contents("split_hash.txt");  
$list = explode("\r\n",$hash);  
$fp = fopen("hadoop2.zip","ab"); 
foreach($list as $value){  
    if(!empty($value)) {  
        $handle = fopen($value,"rb");  
        fwrite($fp,fread($handle,filesize($value)));  
        fclose($handle);  
        unset($handle);  
    }  
}  
fclose($fp);  
echo "ok";    

Will it cost a lot of my memory?

Answer 1

Will it cost a lot of my memory?

it will if you use fread($handle,filesize($value)) to get the whole length of the file for your fread, use fread in smaller chunks per file.

I would change:

fwrite($fp,fread($handle,filesize($value)));

to:

while (!feof($handle)) {
    fwrite($fp,fread($handle,1048576));  
}

so that you are only dealing with 10 megabytes at a time