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SyncSharedMemory::read

PHP function Edit on GitHub ✎

(PECL sync >= 1.1.0)

Copy data from named shared memory

Description

SyncSharedMemory::read(int $start = 0, [int $length])

Copies data from named shared memory.

Parameters

start

The start/offset, in bytes, to begin reading.

Note

If the value is negative, the starting position will begin at the specified number of bytes from the end of the shared memory segment.

length

The number of bytes to read.

Note

If unspecified, reading will stop at the end of the shared memory segment.

If the value is negative, reading will stop the specified number of bytes from the end of the shared memory segment.

Return Values

A string containing the data read from shared memory.

Examples

SyncSharedMemory::__construct() example

php
<?php
// You will probably need to protect shared memory with other synchronization objects.
// Shared memory goes away when the last reference to it disappears.
$mem = new SyncSharedMemory("AppReportName", 1024);
if ($mem->first())
{
    // Do first time initialization work here.
}

$result = $mem->write("report.txt");

$result = $mem->read(3, -4);
var_dump($result);
?>

The above example will output something similar to:

output
string(3) "ort"

See Also

  • SyncSharedMemory::__construct
  • SyncSharedMemory::first
  • SyncSharedMemory::write
  • SyncSharedMemory::read

Source: reference/sync/syncsharedmemory/read.xml · from the official PHP manual (php/doc-en)