XCIV. Shared Memory Functions

介紹

Shmop is an easy to use set of functions that allows PHP to read, write, create and delete UNIX shared memory segments. These functions will not typically work on Windows, as it does not support shared memory. As of Windows 2000 though, enabling the php_shmop.dll in your php.ini will enable this functionality though.

注: In PHP 4.0.3, these functions were prefixed by shm rather than shmop.

需求

建立這個延伸不需要任何外部程式庫。

安裝

To use shmop you will need to compile PHP with the --enable-shmop parameter in your configure line.

執行時期組態

php.ini中沒有定義此延伸的組態指令。

資源類型

預先定義常數

這個延伸沒有定義任何常數。

範例

範例 1. Shared Memory Operations Overview

<?php
   
// Create 100 byte shared memory block with system id if 0xff3
$shm_id = shmop_open(0xff3, "c", 0644, 100);
if(!$shm_id) {
    echo "Couldn't create shared memory segment\n";
}

// Get shared memory block's size
$shm_size = shmop_size($shm_id);
echo "SHM Block Size: ".$shm_size. " has been created.\n";

// Lets write a test string into shared memory
$shm_bytes_written = shmop_write($shm_id, "my shared memory block", 0);
if($shm_bytes_written != strlen("my shared memory block")) {
    echo "Couldn't write the entire length of data\n";
}

// Now lets read the string back
$my_string = shmop_read($shm_id, 0, $shm_size);
if(!$my_string) {
    echo "Couldn't read from shared memory block\n";
}
echo "The data inside shared memory was: ".$my_string."\n";

//Now lets delete the block and close the shared memory segment
if(!shmop_delete($shm_id)) {
    echo "Couldn't mark shared memory block for deletion.";
}
shmop_close($shm_id);
   
?>

內容目錄
shmop_close -- Close shared memory block
shmop_delete -- Delete shared memory block
shmop_open -- Create or open shared memory block
shmop_read -- Read data from shared memory block
shmop_size -- Get size of shared memory block
shmop_write -- Write data into shared memory block