PHP text file auto download giving error headers already sent - php

Question

I am uploading text file and then converting it after conversion I am forcing it to auto download that converted text file, but it's not getting downloaded, giving error Warning: Cannot modify header information - headers already sent
Force download text file PHP code
if (file_exists($fileCreate)) {
header('Content-Description: File Transfer');
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename='.basename($fileCreate));
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate');
header('Pragma: public');
header('Content-Length: ' . filesize($fileCreate));
ob_clean();
flush();
readfile($fileCreate);
exit;
}
}
Full PHP code
<?php
error_reporting(E_ALL & ~E_NOTICE);
if(!empty($_FILES['uploaded_file']))
{
$path = "upload/";
$path = $path . basename( $_FILES['uploaded_file']['name']);
if(move_uploaded_file($_FILES['uploaded_file']['tmp_name'], $path)) {
echo "The file ". basename( $_FILES['uploaded_file']['name']).
" has been uploaded";
} else{
echo "There was an error uploading the file, please try again!";
}
$count = 0;
$fileCreate = 'order-'.date('m-d-Y').".txt";
$myfile = fopen("$fileCreate","w") or die("Unable to open file!");
fwrite($myfile, "1"."\n");
if($file = fopen("$path", "r")){
while(!feof($file)) {
$line = fgets($file);
$keywords = preg_split("/[\s,]+/", $line);
$x = $keywords[2];
$y = 5;
$y .= $x;
$y .= "001";
$date = $keywords[1];
$date1 = str_replace('"','',$date);
$newDate = date("Y/m/d", strtotime($date1));
$y .= str_replace("/", "", $newDate);
$y .= " ";
$fso = $keywords[3];
$fso = str_replace('"','',$fso);
$y .= $keywords[3];
if($fso != "FPO" || $fso != "APO"){
$y .= $keywords[4];
}
$y = str_replace('"','',$y);
$storeValue[$count]=$y;
fwrite($myfile, $y."\n");
$count++;
}
$str = strval($count);
$strlen = strlen($str);
if($strlen == 1){
$footer = 900000;
}
else if($strlen == 2){
$footer = 90000;
}
else if($strlen == 3){
$footer = 9000;
}
else if($strlen == 4){
$footer = 900;
}
else if($strlen == 5){
$footer = 90;
}
else{
$footer = 9;
}
$footer .= $count;
$footerDate = date("Y/m/d");
$footer .= str_replace("/", "", $footerDate);
fwrite($myfile, $footer."\n");
fclose($file);
}
if (file_exists($fileCreate)) {
header('Content-Description: File Transfer');
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename='.basename($fileCreate));
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate');
header('Pragma: public');
header('Content-Length: ' . filesize($fileCreate));
ob_clean();
flush();
readfile($fileCreate);
exit;
}
}
?>
UPDATE: It's fixed by adding output_buffering = ON in php.ini file

Answer 1

Two things.
1) You need to start session immediately after the <?php
2) You session redirect does not work if something output before the session redirect (header location).
What you can do is,
You can use javascript for redirecting.
echo '<script>window.location.replace("http://stackoverflow.com");</script>';
Anyway if you are using sessions, start session on the top of page (session_start()).
<?php
session_start();
error_reporting(E_ALL & ~E_NOTICE);
if(!empty($_FILES['uploaded_file']))

Answer 2

Update
It's fixed by adding output_buffering = ON in php.ini file