Delicious Bookmark this on Delicious Share on Facebook SlashdotSlashdot It! Digg! Digg



PHP : Function Reference : Filesystem Functions : fread

fread

Binary-safe file read (PHP 4, PHP 5)
string fread ( resource handle, int length )

fread() reads up to length bytes from the file pointer referenced by handle. Reading stops when up to length bytes have been read, EOF (end of file) is reached, (for network streams) when a packet becomes available, or (after opening userspace stream) when 8192 bytes have been read whichever comes first.

Parameters

handle

A file system pointer resource that is typically created using fopen().

length

Up to length number of bytes read.

Return Values

Returns the read string or FALSE in case of error.

Examples

Example643.A simple fread() example

<?php
// get contents of a file into a string
$filename = "/usr/local/something.txt";
$handle = fopen($filename, "r");
$contents = fread($handle, filesize($filename));
fclose($handle);
?>


Example644.Binary fread() example

Warning:

On systems which differentiate between binary and text files (i.e. Windows) the file must be opened with 'b' included in fopen() mode parameter.

<?php
$filename
= "c:\\files\\somepic.gif";
$handle = fopen($filename, "rb");
$contents = fread($handle, filesize($filename));
fclose($handle);
?>


Example645.Remote fread() examples

Warning:

When reading from anything that is not a regular local file, such as streams returned when reading remote files or from popen() and fsockopen(), reading will stop after a packet is available. This means that you should collect the data together in chunks as shown in the examples below.

<?php
// For PHP 5 and up
$handle = fopen("http://www.example.com/", "rb");
$contents = stream_get_contents($handle);
fclose($handle);
?>
<?php
$handle
= fopen("http://www.example.com/", "rb");
$contents = '';
while (!
feof($handle)) {
$contents .= fread($handle, 8192);
}
fclose($handle);
?>


Notes

Note:

If you just want to get the contents of a file into a string, use file_get_contents() as it has much better performance than the code above.

Related Examples ( Source code ) » fread













Code Examples / Notes » fread

james

You will probably want to call unpack() if you are trying to read binary data out of a file and you want to interpret the data you read (rather than just passing it through to a browser). For example, if you were reading the header if a binary file format such as a BMP image file you would need to read 4 byte integers out of the binary file.  fread() will return the binary data in a string.  unpack() will let you extract data out of the string an use it as a number.  
<?php
function Read32BitLittleEndianIntFromBinaryFile($FileHandle)
{
   $BinaryData = fread($FileHandle, 4);
   $UnpackedData = unpack("V", $BinaryData);
   return $UnpackedData[1];
}
?>


dave

using the ternary operator as follows seems to be the neatest way of eliminating the 0 length warning (discussed above)...
$content = filesize($file)?fread($handle, filesize($file)):"";


mark

Unfortunately, or maybe fortunately, magic_quotes_runtime setting in php.ini affects this call, even if you specify the bytes count, and even if you specify that the file you're reading is binary (via 'rb' when calling fopen.) So be careful, especially if you're using someone else's library that depends on binary read.

brian

Two quick notes on download prompting...
First, the following line:
<?php
header("Cache-Control: no-cache, must-revalidate");
?>
causes IE6 to prompt you to download the script instead of the output and will fail to connect.  Take out that header and everything works perfectly.
Pragma: no-cache doesn't cause a problem.
Second, Mozilla tries to add .php to the download file name if content-type is application. Changing the content type to the more specific MIME type (such as audio/mpeg) fixes that but causes IE to try its plugins (such as Quicktime).
The fix I found for that to specify attachment instead of inline.  Here's my code: a prompted, small buffer MP3 download:
<?php
function downloadMP3 ($fileDir, $fileName) {
  $completeFilePath=$fileDir.'/'.$fileName;
  header('Pragma: no-cache');
  header("Content-type: audio/mpeg\nContent-Disposition: attachment; filename=\"" . $fileName . "\"\nContent-length: ".(string)(filesize($completeFilePath)));
  $fd=fopen($completeFilePath,'rb');
     while(!feof($fd)) {
        print(fread($fd, 4096));
        flush();
     }
}
?>


fenris_wolf0

To make the effects of the latest PHP version changes of the fread function even more explicit:  the new size limitation of fread -regardless of the filesize one specifies,  in the example below 1024 * 1024- means that if one was  simply reading the contents of a text file from a dynamic URL like so:
<?
 $dp = "http://www.whatever.com/filename.php";
 $buffer = fopen($dp, 'r');
 if (!$buffer)
   {
     echo("

Error: unable to load URL file into $buffer.      Process  aborted.");
     exit();
   }
 $sp = fread($buffer, 1024*1024);
 fclose($buffer);
 highlight_string($sp);
?>
one should from now on use the file_get_contents function, as shown below, to avoid one's text being truncated forcibly.
<?
 $dp = "http://www.whatever.com/filename.php";
 if (!$dp)
   {
     echo("

Error: unable to load URL file into $dp.  Process aborted.");
     exit();
   }
 $sp = file_get_contents($dp);
 highlight_string($sp);
?>
I thought it couldn't hurt to clarify this detail in order to save time for anyone else who is in the same situation as I was tonight when my ISP abruptly upgraded to the latest version of PHP...    :(
Thank you to every previous contributor to this topic.


junk

To force download an mp3 file and/or prevent the mp3 from ending up in the browser's cache. This is very similiar to mindplay's example below.
<?php
@ob_end_clean();
// Only allow mp3 files
$allowedFileType = "mp3";
// Set the filename based on the URL's query string
$theFile = $_REQUEST['theFile'];
// Get info about the file
$f = pathinfo($theFile);
// Check the extension against allowed file types
if(strtolower($f['extension']) != strtolower($allowedFileType)) exit;
// Make sure the file exists
if (!file_exists($theFile)) exit;
// Set headers
header("Pragma: public");
header("Expires: Thu, 19 Nov 1981 08:52:00 GMT");
header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
header("Cache-Control: no-store, no-cache, must-revalidate");
header("Cache-Control: private");
header("Content-Transfer-Encoding: binary");
header("Content-Type: audio/x-mpeg, audio/x-mpeg-3, audio/mpeg3");
// This line causes the browser's "save as" dialog
header( 'Content-Disposition: attachment; filename="'.$f['basename'].'"' );
// Length required for Internet Explorer
header("Content-Length: ".@urldecode(@filesize($theFile)));
// Open file
if (($f = fopen($theFile, 'rb')) === false) exit;
// Push file
while (!feof($f)) {
echo fread($f, (1*(1024*1024)));
flush();
@ob_flush();
}
// Close file
fclose($f);
exit;
?>


webmaster

The following function retrieves a line in a file, regardless of its size, so you won't get an error if the file's size is beyond php's allowed memory limit (the string has to be below however), which is something i was needing for accessing a big log file generated by a webhost. Indexes start at 1 (so $line = 1 means the first line unlike arrays). If the file is small, it would be better to use "file()" however.
<?php
function strpos_count($haystack, $needle, $i = 0) {
while (strpos($haystack,$needle) !== false) {$haystack = substr($haystack, (strpos($haystack,$needle) + 1)); $i++;}
return $i;
}
function getLine($file,$line=1){
$occurence = 0;
$contents = '';
$startPos = -1;
if (!file_exists($file)) return '';
$fp = @fopen($file, "rb");
if (!$fp) return '';
while (!@feof($fp)) {
$str = @fread($fp, 1024);
$number_of_occurences = strpos_count($str,"\n");
if ($number_of_occurences == 0) {if ($start_pos != -1) {$contents .= $str;}}
else {
$lastPos = 0;
for ($i = 0; $i < $number_of_occurences; $i++){
$pos = strpos($str,"\n", $lastPos);
$occurence++;
if ($occurence == $line) {
$startPos = $pos;
if ($i == $number_of_occurences - 1) {$contents = substr($str, $startPos + 1);}
} elseif ($occurence == $line + 1) {
if ($i == 0) {$contents .= substr($str, 0, $pos);} else {$contents = substr($str, $startPos, $pos - $startPos);}
$occurence = 0;
break;
}
$lastPos = $pos + 1;
}
}
}
@fclose($fp);
return $contents;
}
?>


drane

Somewhere between 4.2.3 and 4.3.9, the behaviour of fread() was changed slightly.
When you ask to fread() 0 bytes of data, it spits out a warning  (IMO for no good reason.  I think reading 0 bytes is perfectly valid, if not very useful.)
Consequently, to write warning-free code using fread, you'd have to take code like this:
$content=fread($fd,filesize($myfile));
and replace it with this:
$content='';
$length=filesize($myfile);
if($length) {
 $content = fread($fd, $length);
}
...or this, depending on your taste:
$length=filesize($myfile);
if($length) {
 $content = fread($fd, $length);
} else {
 $content='';
}
(I'm aware that there are much better ways to read in a whole file at once.  I'm just fixing up someone else's code after a server switch and ran across this stupid warning.)


eggbird

Since a fairly recent php (at least it's the case on 5.2.1), fread's memory behaviour changed.
I used to be able to do things like
<?php
$s = fread($fp, 23985798219384);
?>
to read an entire file, as long as I was sure the file would not be more than 23985798219384 bytes long. This worked like a charm (and as documented), but since recently, PHP tries to allocate 23985798219384 bytes no matter what. So, if you get memory allocation errors, replace such code by something like
<?php
$s = fread($fp, filesize($f));
?>
or even
<?php
$s = file_get_contents($f);
?>
.


c97

Simple script to limit browser download speed using fread function.
<?php
$file = "test.mp3"; // file to be send to the client
$speed = 8.5; // 8,5 kb/s download rate limit
if(file_exists($file) && is_file($file)) {
header("Cache-control: private");
header("Content-Type: application/octet-stream");
header("Content-Length: ".filesize($file));
header("Content-Disposition: filename=$file" . "%20");
flush();
$fd = fopen($file, "r");
while(!feof($fd)) {
echo fread($fd, round($speed*1024));
flush();
sleep(1);
}
fclose ($fd);
}
?>


james

Several of these examples use a Content-Disposition header to force the browser to save a file but then they specify the file name without quotes. This will cause problems for some browsers (Mozilla Fire Fox) if the file name contains a space.  You must put quotes around the name if you want to work reliably for all files in all browsers.
<?php
header ("Content-Disposition: attachment; filename=$theFileName"); // bad
header ("Content-Disposition: attachment; filename=\"$theFileName\""); // good
?>


kai

reading from a socket stream can be different to the
behaviour expected, since you have not set
stream_set_blocking to 1.
sample source:
$fp = fsockopen ($server, $port, $errno, $errstr, $socket_timeout);
$header = '';
do {
$header.=fread($fp,1);
$i++;
} while (!preg_match('/\\r\\n\\r\\n$/', $header) && $i < $maxheaderlenth);
preg_match('/Content\\-Length:\\s+([0-9]*)\\r\\n/', $header,$matches);
$buffer = fread($this->_fp, $matches[1]);
if i.e. the content length is 50000 and the responding server is to slow
(means 50000 are not completely sent when fread is called)
you'll only receive the number of bytes sent by the
responding server at the time fread is called.
fread will not wait for any data to complete the given size.
as described in user notes on stream_set_blocking there
seems to be a bug using stream_set_blocking.
a workaround - well, not the best way - is to read
the response split to 1 byte
instead of
$buffer = fread($this->_fp, $matches[1]);
you'd write
$buffer = '';
for($i = 0; $i < $matches[1]; $i++){
$buffer .= fread($this->_fp, 1);
}
it several tests this seems like it works.


mightymrj

Problem: mime attachments sending as blank or almost completely blank documents (all data is lost)
Explanation: After a couple days of trying to mime pdf attachments without losing all data, I finally came across this function in some obsolete obscure post:
set_magic_quotes_runtime()
This is set to on by default in the machine, and it causes fread() and/or base64_encode() (both used in most mime examples I've seen) to read or encrypt binary without slashes for special characters.  This causes sent files to process incorrectly, breaking, thus truncating most of the data in the file.  
Fix: pass 0 to this function and it will do a one time turn off while your code executes.
example:
<?php
  set_magic_quotes_runtime(0);
?>
This can also been turned off in the php.ini file, but I'm not sure what uses that setting or what the consequences might be.
info:
  http://us2.php.net/manual/en/function.set-magic-quotes-runtime.php


sbedbergat

PHP seems to preallocate a buffer of length <length> - so, you may need to increase your memory_limit if you use a large <length>, even though the actual bytecount read is small.
(this is on php 4.1.1/Solaris 8; your mileage may vary).


mrhappy

Just a note for anybody trying to implement a php handled download script -
We spent a long time trying to figure out why our code was eating system resources on large files.. Eventually we managed to trace it to output buffering that was being started on every page via an include.. (It was attempting to buffer the entire 600 Megs or whatever size *before* sending data to the client) if you have this problem you may want to check that first and either not start buffering or close that in the usual way :)
Hope that prevents somebody spending hours trying to fix an obscure issue.
Regards :)


ibis

If, like me, you're in the habit of using fopen("http://...") and fread for pulling fairly large remote files, you may find that the upgrade to PHP5 (5.0.2 on Win2000/IIS5) causes fread to top out at about 8035 bytes. PHP5 RC2 with identical php.ini settings did not exhibit this behaviour (I was using this for testing). Irritating for me because I was using simple_xml_load to load the file contents as XML, and the problem initially appeared to be that function.
Solution - swap over to file_get_contents or use the loop suggested on the documentation above (see Warning).


richard dale richard

If you use any of the above code for downloadinng files, Internet Explorer will change the filename if it has multiple periods in it to something with square brackets.  To work around this, we check to see if the User Agent contains MSIE and rewrite the necessary periods as %2E
<?
# eg. $filename="setup.abc.exe";
if (strstr($_SERVER['HTTP_USER_AGENT'], "MSIE")) {
# workaround for IE filename bug with multiple periods / multiple dots in filename
# that adds square brackets to filename - eg. setup.abc.exe becomes setup[1].abc.exe
$iefilename = preg_replace('/\./', '%2e', $filename, substr_count($filename, '.') - 1);
header("Content-Disposition: attachment; filename=$iefilename" );
} else {
header("Content-Disposition: attachment; filename=$filename");
}
?>


mail

I wrote a simple function for grabbing binary files from the web.
<?php
function wwwcopy($file,$nfile)
{
   $fp = @fopen($file,"rb");
   while(!feof($fp))
   {
       $cont.= fread($fp,1024);
   }
   fclose($fp);
   $fp2 = @fopen($nfile,"w");
   fwrite($fp2,$cont);
   fclose($fp2);
}
?>


dvsoftware

I was trying to implement resume support in download script, and i have finnaly succeded. here is the script:
<?php
function dl_file_resume($file){
  //First, see if the file exists
  if (!is_file($file)) { die("<b>404 File not found!</b>"); }
  //Gather relevent info about file
  $len = filesize($file);
  $filename = basename($file);
  $file_extension = strtolower(substr(strrchr($filename,"."),1));
  //This will set the Content-Type to the appropriate setting for the file
  switch( $file_extension ) {
    case "exe": $ctype="application/octet-stream"; break;
    case "zip": $ctype="application/zip"; break;
    case "mp3": $ctype="audio/mpeg"; break;
    case "mpg":$ctype="video/mpeg"; break;
    case "avi": $ctype="video/x-msvideo"; break;
    //The following are for extensions that shouldn't be downloaded (sensitive stuff, like php files)
    case "php":
    case "htm":
    case "html":
    case "txt": die("<b>Cannot be used for ". $file_extension ." files!</b>"); break;
    default: $ctype="application/force-download";
  }
  //Begin writing headers
  header("Pragma: public");
  header("Expires: 0");
  header("Cache-Control:");
  header("Cache-Control: public");
  header("Content-Description: File Transfer");
 
  //Use the switch-generated Content-Type
  header("Content-Type: $ctype");
$filespaces = str_replace("_", " ", $filename);
//if your filename contains underscores, you can replace them with spaces
 $header='Content-Disposition: attachment; filename='.$filespaces.';';
  header($header );
  header("Content-Transfer-Encoding: binary");
 $size=filesize($file);
//check if http_range is sent by browser (or download manager)
  if(isset($_ENV['HTTP_RANGE'])) {
list($a, $range)=explode("=",$_ENV['HTTP_RANGE']);
//if yes, download missing part
str_replace($range, "-", $range);
$size2=$size-1;
header("Content-Range: $range$size2/$size");
$new_length=$size2-$range;
header("Content-Length: $new_length");
/if not, download whole file
} else {
$size2=$size-1;
header("Content-Range: bytes 0-$size2/$size");
header("Content-Length: ".$size2);
}
//open the file
$fp=fopen("$file","r");
//seek to start of missing part
fseek($fp,$range);
//start buffered download
while(!feof($fp))
{
//reset time limit for big files
set_time_limit();
print(fread($fp,1024*8));
flush();
}
fclose($fp);
 
  exit;

}
?>
EXAMPLE
<?php
dl_file_resume("somefile.mp3");
?>
please write if you find any errors, i have tested this only with mp3 files, but others should be fine


yellow1912

I tried to use the download resume script below, but it put extreme load on the server for just 1 download only (the file is around 200MB).
Be carefull when you test the script on your server. I'll fgets, or other functions and see if it works.


matt

I thought I had an issue where fread() would fail on files > 30M in size. I tried a file_get_contents() method with the same results. The issue was not reading the file, but echoing its data back to the browser.
Basically, you need to split up the filedata into manageable chunks before firing it off to the browser:
<?php
$total     = filesize($filepath);
$blocksize = (2 << 20); //2M chunks
$sent      = 0;
$handle    = fopen($filepath, "r");
// Push headers that tell what kind of file is coming down the pike
header('Content-type: '.$content_type);
header('Content-Disposition: attachment; filename='.$filename);
header('Content-length: '.$filesize * 1024);

// Now we need to loop through the file and echo out chunks of file data
// Dumping the whole file fails at > 30M!
while($sent < $total){
echo fread($handle, $blocksize);
$sent += $blocksize;
}

exit(0);
?>
Hope this helps someone!


rob

I spent a while trying to get this to work so I thought I'd share.
Here's how to read a remote binary file using fread.
<?php
$fp = fopen("http://www.site.com/img.jpg", "rb");
if($fp){
while(!feof($fp)) {
    $img = $img . fread($fp, 1024);
}
}
?>
This will read the contents of the file into the var $img 1024 bytes at a time.  I used that number because it seemed safe, but you can increment it all you want I guess.
I don't know if everyone but me gets this, but I thought I'd share since I didn't see anything like it out there.


xjust

i fixed the resume download function since there were few bugs in it. here it goes
changes:
- i added "partial content" header
- added "bytes" to the first content-range header
- changed _ENV to _SERVER on HTTP_RANGE
best regards from xjust.
function dl_file_resume($file){
  //First, see if the file exists
  if (!is_file($file)) { die("<b>404 File not found!</b>"); }
  //Gather relevent info about file
  $len = filesize($file);
  $filename = basename($file);
  $file_extension = strtolower(substr(strrchr($filename,"."),1));
  //This will set the Content-Type to the appropriate setting for the file
  switch( $file_extension ) {
    case "exe": $ctype="application/octet-stream"; break;
    case "zip": $ctype="application/zip"; break;
    case "mp3": $ctype="audio/mpeg"; break;
    case "mpg":$ctype="video/mpeg"; break;
    case "avi": $ctype="video/x-msvideo"; break;
    //The following are for extensions that shouldn't be downloaded (sensitive stuff, like php files)
    case "php":
    case "htm":
    case "html":
    case "txt": die("<b>Cannot be used for ". $file_extension ." files!</b>"); break;
    default: $ctype="application/force-download";
  }
  //Begin writing headers
//   header("Pragma: public");
//   header("Expires: 0");
  header("Cache-Control:");
  header("Cache-Control: public");
//   header("Content-Description: File Transfer");
 
  //Use the switch-generated Content-Type
  header("Content-Type: $ctype");
$filespaces = str_replace("_", " ", $filename);
//if your filename contains underscores, you can replace them with spaces
//   $header='Content-Disposition: attachment; filename='.$filespaces;
  header($header );
//
header("Accept-Ranges: bytes");
//   header("Content-Transfer-Encoding: binary");
 $size=filesize($file);
//check if http_range is sent by browser (or download manager)
   if(isset($_SERVER['HTTP_RANGE'])) {
list($a, $range)=explode("=",$_SERVER['HTTP_RANGE']);
//if yes, download missing part
str_replace($range, "-", $range);
$size2=$size-1;
$new_length=$size2-$range;
header("HTTP/1.1 206 Partial Content");
header("Content-Length: $new_length");
header("Content-Range: bytes $range$size2/$size");
} else {
$size2=$size-1;
header("Content-Range: bytes 0-$size2/$size");
header("Content-Length: ".$size2);
}
//open the file
$fp=fopen("$file","r");
//seek to start of missing part
fseek($fp,$range);
//start buffered download
while(!feof($fp))
{
//reset time limit for big files
set_time_limit(0);
print(fread($fp,1024*8));
flush();
}
fclose($fp);
 
  exit;
   
}


m

Here's a function for sending a file to the client - it may look more complicated than necessary, but has a number of advantages over simpler file sending functions:
- Works with large files, and uses only an 8KB buffer per transfer.
- Stops transferring if the client is disconnected (unlike many scripts, that continue to read and buffer the entire file, wasting valuable resources) but does not halt the script
- Returns TRUE if transfer was completed, or FALSE if the client was disconnected before completing the download - you'll often need this, so you can log downloads correctly.
- Sends a number of headers, including ones that ensure it's cached for a maximum of 2 hours on any browser/proxy, and "Content-Length" which most people seem to forget.
(tested on Linux (Apache) and Windows (IIS5/6) under PHP4.3.x)
Note that the folder from which protected files will be pulled, is set as a constant in this function (/protected) ... Now here's the function:
<?php
function send_file($name) {
 ob_end_clean();
 $path = "protected/".$name;
 if (!is_file($path) or connection_status()!=0) return(FALSE);
 header("Cache-Control: no-store, no-cache, must-revalidate");
 header("Cache-Control: post-check=0, pre-check=0", false);
 header("Pragma: no-cache");
 header("Expires: ".gmdate("D, d M Y H:i:s", mktime(date("H")+2, date("i"), date("s"), date("m"), date("d"), date("Y")))." GMT");
 header("Last-Modified: ".gmdate("D, d M Y H:i:s")." GMT");
 header("Content-Type: application/octet-stream");
 header("Content-Length: ".(string)(filesize($path)));
 header("Content-Disposition: inline; filename=$name");
 header("Content-Transfer-Encoding: binary\n");
 if ($file = fopen($path, 'rb')) {
   while(!feof($file) and (connection_status()==0)) {
     print(fread($file, 1024*8));
     flush();
   }
   fclose($file);
 }
 return((connection_status()==0) and !connection_aborted());
}
?>
And here's an example of using the function:
<?php
if (!send_file("platinumdemo.zip")) {
die ("file transfer failed");
// either the file transfer was incomplete
// or the file was not found
} else {
// the download was a success
// log, or do whatever else
}
?>
Regards,
Rasmus Schultz


blagovest buyukliev

Having tried to reliably transfer large amounts of binary data over a latent network, I found out that fread()/fwrite() should never be trusted to read/write the whole block with the exact length specified, even in blocking mode, even for small block lengths.
I came up with these two functions, fully-replaceable and reliable alternatives of fread()/fwrite() in a socket context:
<?php
function fullwrite ($sd, $buf) {
 $total = 0;
 $len = strlen($buf);
 while ($total < $len && ($written = fwrite($sd, $buf))) {
   $total += $written;
   $buf = substr($buf, $written);
 }
 return $total;
}
function fullread ($sd, $len) {
 $ret = '';
 $read = 0;
 while ($read < $len && ($buf = fread($sd, $len - $read))) {
   $read += strlen($buf);
   $ret .= $buf;
 }
 return $ret;
}
?>
The functions are "greedy", i.e. trying to read/write as much data as possible at once. If the call to fread()/fwrite() reads/writes less than expected, then the next iteration eats up the remainder. Very smart as only the largest possible chunks are read/written.
Only in case of a broken pipe fullread()/fullwrite() return less than the specified length. Otherwise it is guaranteed that upon termination
strlen(fullread($sd, $len)) == $len
and
fullwrite($sd, $buf) == strlen($buf)
Works perfectly with a socket descriptor returned from stream_socket_client() or fsockopen().
Greetings from Rousse, Bulgaria.


heikki dot korpela

Fread is binary-safe IF AND ONLY IF you don't use magic-quotes. If you do, all null bytes will become \0, and you might get surprising results when unpacking.
That is, you would do something like
<?php
set_magic_quotes_runtime(0);
?>
before fread()
and something like
<?php
set_magic_quotes_runtime(get_magic_quotes_gpc()) after.
?>
And, after fread, an unpack would be needed, of course. Surprisingly, pack(), however, does not work quite like in Perl (or perhaps I'm just missing something here) - you can't pack an array directly, but instead you'll have to pack each element seperately to the string:
<?php
foreach ($data as $dec) {
 $data_output .= pack("C*", $dec);
}
?>


squeegee

fread also works for fsockopen's that are open-ended (no feof) if you know how the last packet for a particular set of data should end. For example, if you sent a command to an nntp server, the reply from the server would end with a dot and a carriage return/linefeed. The connection still stays open for more commands, but doing it this way is more efficient than doing line-by-line fgets until you get to the end of the reply.
<?php
if(($res=nntp_cmd($conn,"BODY $msgid",222))===false){
   continue;
}else{
   $contents='';
   while(1){
       $packet=fread($conn,8192);
       $contents.=$packet;
       if(substr($packet,-3)==".\r\n")break;
   }
   // do something with $contents
}
?>


ethanh

For reading from a specified point in the file, use:
<?php
$fp=fopen("$filename","r");
fseek($fp,$numpoint);
$content=fread($fp,filesize("$filename"));
fclose($fp);
?>
For doing the same with an url-based file, use jeichorn@mail.com's solution and substr it.


planetiss

For download the big files (more than 8MB), you must used ob_flush() because the function flush empty the Apache memory and not PHP memory.
And the max size of PHP memory is 8MB, but ob_flush is able to empty the PHP memory.
header('Content-Type: application/force-download');
header ("Content-Length: " . filesize($file));
header ("Content-Disposition: attachment; filename=$theFileName");
  $fd = fopen($file, "r");
  while(!feof($fd))
 {
      echo fread($fd, 4096);
      ob_flush();
     
  }


sheyh

Following code which was given as official example can lead to infinite loop.
In case of running from command line and there is no Internet connection, fopen will fail by script timeout, however after that "!feof($handle)" will never be true.
The result will be script displaying infinite warnings and taking 10-20% cpu and it will not stop unless killed.
<?php
$handle = fopen("http://www.example.com/", "r");
$contents = '';
while (!feof($handle)) {
 $contents .= fread($handle, 8192);
}
fclose($handle);
?>
I belive correct example should be:
<?php
$handle = fopen("http://www.example.com/", "r");
$contents = '';
if($handle)
{
while (!feof($handle)) {
  $contents .= fread($handle, 8192);
}
fclose($handle);
}
?>


aubfre

Changing the value of $length may yield to different download speeds when serving a file from a script.
I was not able to max out my 10mbps connection when 4096 was used. I found out that using 16384 would use all the available bandwidth.
When outputing binary data with fread, do not assume that 4096 or 8192 is the optimal value for you. Do some benchmarks by downloading files through your script.


dhani dot novan

Better version from dl_file_resume
i just compile from past post notes here
Change:
1. Fix Critical BUG : (file exe will corrupt because the size is minus one)
before: header("Content-Length: ".$size2);
after: header("Content-Length: ".$size);
2. closequote filename
before: header("Content-Disposition: attachment; filename=$filename");
after: header("Content-Disposition: attachment; filename=\"$filename\"");
3. read as binary
before: $fp=fopen("$file","r");
after: $fp=fopen("$file","rb");
4. use ob_flush
5. workaround for IE filename bug
<?php
function dl_file_resume($file){
//First, see if the file exists
if (!is_file($file)) { die("<b>404 File not found!</b>"); }

//Gather relevent info about file
$len = filesize($file);
$filename = basename($file);
$file_extension = strtolower(substr(strrchr($filename,"."),1));

//This will set the Content-Type to the appropriate setting for the file
switch( $file_extension ) {
case "exe": $ctype="application/octet-stream"; break;
case "zip": $ctype="application/zip"; break;
case "mp3": $ctype="audio/mpeg"; break;
case "mpg":$ctype="video/mpeg"; break;
case "avi": $ctype="video/x-msvideo"; break;
default: $ctype="application/force-download";
}

//Begin writing headers
header("Cache-Control:");
header("Cache-Control: public");

//Use the switch-generated Content-Type
header("Content-Type: $ctype");
if (strstr($_SERVER['HTTP_USER_AGENT'], "MSIE")) {
# workaround for IE filename bug with multiple periods / multiple dots in filename
# that adds square brackets to filename - eg. setup.abc.exe becomes setup[1].abc.exe
$iefilename = preg_replace('/\./', '%2e', $filename, substr_count($filename, '.') - 1);
header("Content-Disposition: attachment; filename=\"$iefilename\"");
} else {
header("Content-Disposition: attachment; filename=\"$filename\"");
}
header("Accept-Ranges: bytes");

$size=filesize($file);
//check if http_range is sent by browser (or download manager)
if(isset($_SERVER['HTTP_RANGE'])) {
list($a, $range)=explode("=",$_SERVER['HTTP_RANGE']);
//if yes, download missing part
str_replace($range, "-", $range);
$size2=$size-1;
$new_length=$size2-$range;
header("HTTP/1.1 206 Partial Content");
header("Content-Length: $new_length");
header("Content-Range: bytes $range$size2/$size");
} else {
$size2=$size-1;
header("Content-Range: bytes 0-$size2/$size");
header("Content-Length: ".$size);
}
//open the file
$fp=fopen("$file","rb");
//seek to start of missing part
fseek($fp,$range);
//start buffered download
while(!feof($fp)){
//reset time limit for big files
set_time_limit(0);
print(fread($fp,1024*8));
flush();
ob_flush();
}
fclose($fp);
exit;
}
?>


aidan

As of PHP 5.0.0 and PHP 4.3.8, fread($stream, 2048) will only grab 1 packet worth of data from the buffer in a TCP/IP or UDP stream.
Note: 2048 is the suggested size to make sure you get all of one packet, any size larger than that will still have the same result


fpinho

After using the suggested function from Rasmus Schultz : mindplay(at)mindplay(dot)dk, I've just noticed that people trying to download big files with a slow connection would get download stopped after exactly 60seconds -> the max execution time set with php.ini.
I suggest using a bigger buffer (1024x1024), or maybe resetting the time limit within the 'while' cicle with:
  set_time_limit(0);
The cicle would go like this:
  while(!feof($file) and (connection_status()==0)) {
    print(fread($file, 1024*1024));
    set_time_limit(0);
    flush();
  }
Frederico Pinho


admin

According: dvsoftware at gmail dot com
Hi all, the sript by dvsoftware is quit handy. But I had a lot of problems to read the dam.. file. Every file. I was using a Windows Platform, maybe that was the mistake.
Annyway, I had to read the file in one session:
<?
:
:
while(!feof($fp))
{
//print (fread($fp,1024*8)); //4096 //1024*8
print fread($fp,$size);
flush();
}
fclose($fp);
:
:
?>


adamgamble

/*
geoCode($address)
Accepts an address in the form of
999 Geocode Dr. New York, Ny 10108
returns array with lat and lon
*/
function geoCode($address) {
   $gaddress = "http://maps.google.com?q=" . urlencode($address);
   $handle = fopen($gaddress, "r");
   $contents = '';
    while (!feof($handle)) {
        $contents .= fread($handle, 8192);
    }
    fclose($handle);
    ereg('<center lat="([0-9.-]{1,})" lng="([0-9.-]{1,})"/>', $contents, $regs);
    $returnData['lat'] = $regs[1];
    $returnData['lon'] = $regs[2];
    return $returnData;
}
print_r(geoCode("1064 Georgetown ln. Birmingham, Al 35217"));


tchapin

<?php
// Usage: <a href="download.php?file=test.txt&category=test">Download</a>  
// Path to downloadable files (will not be revealed to users so they will never know your file's real address)
$hiddenPath = "secretfiles/";
// VARIABLES
if (!empty($_GET['file'])){
$file = str_replace('%20', ' ', $_GET['file']);
$category = (!empty($_GET['category'])) ? $_GET['category'] . '/' : '';
}
$file_real     = $hiddenPath . $category . $file;
$ip            = $_SERVER['REMOTE_ADDR'];
// Check to see if the download script was called
if (basename($_SERVER['PHP_SELF']) == 'download3.php'){
if ($_SERVER['QUERY_STRING'] != null){
// HACK ATTEMPT CHECK
// Make sure the request isn't escaping to another directory
if (substr($file, 0, 1) == '.' || strpos($file, '..') > 0 || substr($file, 0, 1) == '/' || strpos($file, '/') > 0){
// Display hack attempt error
echo("Hack attempt detected!");
die();
}
// If requested file exists
if (file_exists($file_real)){
// Get extension of requested file
$extension = strtolower(substr(strrchr($file, "."), 1));
// Determine correct MIME type
switch($extension){
case "asf":     $type = "video/x-ms-asf";                break;
case "avi":     $type = "video/x-msvideo";               break;
case "exe":     $type = "application/octet-stream";      break;
case "mov":     $type = "video/quicktime";               break;
case "mp3":     $type = "audio/mpeg";                    break;
case "mpg":     $type = "video/mpeg";                    break;
case "mpeg":    $type = "video/mpeg";                    break;
case "rar":     $type = "encoding/x-compress";           break;
case "txt":     $type = "text/plain";                    break;
case "wav":     $type = "audio/wav";                     break;
case "wma":     $type = "audio/x-ms-wma";                break;
case "wmv":     $type = "video/x-ms-wmv";                break;
case "zip":     $type = "application/x-zip-compressed";  break;
default:        $type = "application/force-download";    break;
}
// Fix IE bug [0]
$header_file = (strstr($_SERVER['HTTP_USER_AGENT'], 'MSIE')) ? preg_replace('/\./', '%2e', $file, substr_count($file, '.') - 1) : $file;
// Prepare headers
header("Pragma: public");
header("Expires: 0");
header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
header("Cache-Control: public", false);
header("Content-Description: File Transfer");
header("Content-Type: " . $type);
header("Accept-Ranges: bytes");
header("Content-Disposition: attachment; filename=\"" . $header_file . "\";");
header("Content-Transfer-Encoding: binary");
header("Content-Length: " . filesize($file_real));
// Send file for download
if ($stream = fopen($file_real, 'rb')){
while(!feof($stream) && connection_status() == 0){
//reset time limit for big files
set_time_limit(0);
print(fread($stream,1024*8));
flush();
}
fclose($stream);
}
}else{
// Requested file does not exist (File not found)
echo("Requested file does not exist");
die();
}
}
}
?>


Change Language


Follow Navioo On Twitter
basename
chgrp
chmod
chown
clearstatcache
copy
delete
dirname
disk_free_space
disk_total_space
diskfreespace
fclose
feof
fflush
fgetc
fgetcsv
fgets
fgetss
file_exists
file_get_contents
file_put_contents
file
fileatime
filectime
filegroup
fileinode
filemtime
fileowner
fileperms
filesize
filetype
flock
fnmatch
fopen
fpassthru
fputcsv
fputs
fread
fscanf
fseek
fstat
ftell
ftruncate
fwrite
glob
is_dir
is_executable
is_file
is_link
is_readable
is_uploaded_file
is_writable
is_writeable
lchgrp
lchown
link
linkinfo
lstat
mkdir
move_uploaded_file
parse_ini_file
pathinfo
pclose
popen
readfile
readlink
realpath
rename
rewind
rmdir
set_file_buffer
stat
symlink
tempnam
tmpfile
touch
umask
unlink
eXTReMe Tracker