Description:
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Hi, i have a problem in downloading pdf files that is when i click the download button it just download a text file contains unreadable and unrecognizable words and numbers , so can any one help me to solve this problem;
 my code to download a pdf file is :

Test script:
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    $DOCUMENT_ROOT=$_SERVER['DOCUMENT_ROOT'];
	  
    $root_file = "$DOCUMENT_ROOT"."mysite2/downbooks/";
    $book_name = str_replace(" ","",$book_name);
    $down_url = $root_file.$book_name;
    
    header('Prgrama: public');
    header('Content-Type: application/pdf');
    header('Content-Type: application/force-download');
    header('Content-Type: application/octet-stream');
    header('Content-Type: application/download');
    header('Content-disposition: attachment; filename='.$book_name.";");	  
    header('Content-Transfer-Encoding: binary');
    header('Content-Length: ' . filesize($down_url));
    @readfile($book_name.".pdf");
    exit;

Expected result:
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download a pdf file

Actual result:
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i just get a plain text file contains unreadable and unrecognizable words and numbers.