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stream_get_contents

(PHP 5, PHP 7, PHP 8)

stream_get_contentsTransfiere el resto de un flujo a una cadena

Descripción

stream_get_contents(resource $handle, int $maxlength = -1, int $offset = -1): string

Idéntica a file_get_contents(), excepto que stream_get_contents() opera sobre un recurso de flujo ya abierto y devuelve el resto del contenido en una cadena, hasta maxlength bytes y comenzando por el offset especificado.

Parámetros

handle (resource)

Un recurso de flujo (p.ej. devuelto desde fopen())

maxlength (integer)

El máximo de bytes a leer. Por defecto es -1 (lee todo el buffer restante).

offset (integer)

Busca el índice especificado antes de leer. Si este número es negativo, no se hará ninguna búsqueda y la lectura comenzará desde la posición actual.

Valores devueltos

Devuelve una cadena o false en caso de error.

Historial de cambios

Versión Descripción
5.1.0 Se añadió el parámetro offset.

Ejemplos

Ejemplo #1 Ejemplo de stream_get_contents()

<?php

if ($stream = fopen('http://www.example.com', 'r')) {
// imprimir toda la página empezando por el índice 10
echo stream_get_contents($stream, -1, 10);

fclose($stream);
}


if (
$stream = fopen('http://www.example.net', 'r')) {
// imprimir los 5 primeros bytes
echo stream_get_contents($stream, 5);

fclose($stream);
}

?>

Notas

Nota: Esta función es segura binariamente.

Ver también

  • fgets() - Obtiene una línea desde el puntero a un fichero
  • fread() - Lectura de un fichero en modo binario seguro
  • fpassthru() - Escribe toda la información restante de un puntero a un archivo

add a note

User Contributed Notes 4 notes

up
17
vasiliy at hotger dot com
11 years ago
It is important to know that stream_get_contents behaves differently with different versions of PHP. Consider the following

<?php

$handle
= fopen('file', 'w+'); // truncate + attempt to create
fwrite($handle, '12345'); // file position > 0
rewind($handle); // position = 0
$content = stream_get_contents($handle); // file position = 0 in PHP 5.1.6, file position > 0 in PHP 5.2.17!
fwrite($handle, '6789');
fclose($handle);

/**
*
* 'file' content
*
* PHP 5.1.6:
* 67895
*
* PHP 5.2.17:
* 123456789
*
*/
?>

As a result, stream_get_contents() affects file position in 5.1, and do not affect file position in 5.2 or better.
up
11
clarck dot smith at gmail dot com
12 years ago
In that case when stream_get_contents/fread/fgets or other stream reading functions block indefinitely your script because they don't reached the limit of bytes to read use the socket_get_meta_data function to figure out the number of the bytes to read. It returns an array that contains a key named 'unread_bytes' and then pass that number to your favourite stream reading functions second parameter to read from the stream.

Maybe a good workaround to use the stream_select function, and set the socket to non-blocking mode with the use of stream_set_blocking($stream, 0). In this case the socket reading functions work properly.

Cheers, Ervin
up
4
m rahman
13 years ago
When omitting the parameter $maxlength, any received bytes are stacked up until the underlying stream is not readable anymore, the the function returns that stack in one piece.
up
-1
fearpro13 at gmail dot com
2 months ago
It states that $length parameter which value is null is intended to read all remaining contents from $stream
However, example listed under docs uses -1 as $length parameter to achieve such behavior

Recently i had to start few commands from php7.4 and read content from them, proc_open was used to create processes.
Both output[1] and error[2] pipes were set to non-blocking mode. For some unknown reason sometimes process error[2] channel was available, sometimes not(it was empty string).

After some investigation it was found that stream_get_contents works just great with -1 as a $length value instead of null if you are trying to get all remaining buffer.
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