fgets is faster but stream_get_line is more useful in a tcp server scripts.
when fgets reads some bytes from socket, where EOF is reached, it returns bool(false) same as stream_get_line
BUT if remote client drops connection, and server script will try to read some data with function fgets, function will return bool(false), and stream_get_line will return string(0) ""
so you can detect remote client disconnection with stream_get_line, and cannot with fgets
stream_get_line
(PHP 5)
stream_get_line — Obtiene una línea del recurso de flujo hasta un delimitador dado
Descripción
Obtiene una linea desde el gestor dado.
La lectura finaliza cuando hayan sido leídos length bytes, cuando se encuentre la cadena especificada por ending (la cuál no está incluida en el valor devuelto), o sobre EOF (lo que suceda primero).
Esta función es casi indéntica a fgets() excepto que permite delimitadores de fin de línea distintos a los habituales \n, \r, y \r\n, y no devuelve el delimitador mismo.
Parámetros
- handle
-
Un gestor de archivo válido.
- length
-
El número de bytes a leer desde el gestor.
- ending
-
Un delimitador de cadena opcional.
Valores devueltos
Devuelve una cadena de hasta length bytes leídos desde el archivo apuntado por handle.
Si ocurre un error, devuelve FALSE.
If the "ending" is a string, there are cases where the function doesn't return the correct value for the first time it is called. Don't be shocked if you find it returning a string value of upto "length" that includes the "ending". (See bug #44607)
If the "ending" is just a single character, the function would always work correctly. ("\n" is a single character)
Temporarily, until this is fixed, the below function can be used:
<?php
function istream_get_line(&$fp, $length, $end) {
$current = ftell($fp);
$str = fread($fp, $length);
$i = strpos($str, $end);
if ($i === FALSE) {
return $str;
} else {
fseek($fp, $current + $i + strlen($end));
return substr($str, 0, $i);
}
}
?>
I've spent quite a while trying to get stream_get_line to get a chunk encoded html file and to finish correctly at the end so that I can pipeline requests.
This is the function I have come up with.
<?php
function getURLContents($url, $ip, $port, $ssl = false, $closeConnection = false)
{
if ($ssl)
$ssl = 'ssl://';
else
$ssl = '';
$fp = pfsockopen($ssl.$ip, $port, $errno, $errstr, MAX_TIME_TO_START_CONNECTION);
if ($fp)
{
$out = 'GET '.$url." HTTP/1.1\r\n";
$out .= 'Host: '.$ip.':'.$port."\r\n";
if ($closeConnection)
$out .= "Connection: close\r\n";
else
$out .= "Connection: keep-alive\r\n";
$out .= "\r\n";
if (!fwrite($fp, $out))
{
echo 'Problem writing to socket, opening a new connection.';
fclose($fp);
$fp = pfsockopen($ssl.$ip, $port, $errno, $errstr, MAX_TIME_TO_START_CONNECTION);
fwrite($fp, $out);
}
$theData = '';
$notDone = true;
stream_set_blocking($fp, 0);
$startTime = time();
$lastTime = $startTime;
while (!feof($fp) && !$done && (($startTime + MAX_TIME_FOR_THE_RESPONSE) > time()))
{
usleep(100);
$theNewData = stream_get_line($fp, 1024, "\n");
$theData .= $theNewData;
$done = (trim($theNewData) === '0');
}
}
else
{
echo 'ERROR CONNECTING TO '.$ip.':'.$port;
return false;
}
if ($closeConnection)
fclose($fp);
return $theData;
}
?>
My testing has found this function to be dramatically faster than fgets on PHP 5.1.14. The difference is probably due to how buffering is used internally. Compare the following:
<?php
// reads 10,000 lines in 27 seconds
while (!feof($handle)) {
$line = fgets($handle, 1000000);
}
?>
vs.
<?php
// reads 10,000 lines in 0.5 seconds
while (!feof($handle)) {
$line = stream_get_line($handle, 1000000, "\n");
}
?>
In version 5.0.4 using this funtion and then calling ftell($stream) would give you the position up to but not including the "ending" string.
When I rev'd to PHP version 5.1.2, calling this function then using ftell($stream) would give the position up to AND including the "ending" string
for example, parsing HTTP responses.
The response from apache using curl....
------------------------------------------------------------
HTTP/1.1 200 OK
Date: Tue, 18 Apr 2006 20:54:59 GMT
Server: Apache/1.3.33 (Unix) PHP/5.0.4 mod_ssl/2.8.22 OpenSSL/0.9.7e
X-Powered-By: PHP/5.0.4
Transfer-Encoding: chunked
Content-Type: text/html
<html><body>test</body></html>
-------------------------------------------------------------
The code:
<?php
$headers = stream_get_line($in,4096,"\r\n\r\n");
fseek ($in,ftell($in)+4);
while (!feof($in)){
fputs ($out,stream_get_line($in,4096,''));
}
?>
prior to my 5.0.4 this worked perfectly, trimming the \r\n\r\n section of the HTTP response and seperating the top into the $headers string, and the rest was placed into the file handle $out.
using php 5.1.2, the above code chopps off the first 4 bytes of the HTTP response and puts
l><body>test</body></html>
into $out.
