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shmop_write

(PHP 4 >= 4.0.4, PHP 5, PHP 7)

shmop_writeWrite data into shared memory block

Description

shmop_write ( Shmop $shmop , string $data , int $offset ) : int

shmop_write() will write a string into shared memory block.

Parameters

shmop

The shared memory block identifier created by shmop_open()

data

A string to write into shared memory block

offset

Specifies where to start writing data inside the shared memory segment.

Return Values

The size of the written data.

Changelog

Version Description
8.0.0 Prior to PHP 8.0.0, FALSE was returned on failure.
8.0.0 shmop expects a Shmop instance now; previously, a resource was expected.

Examples

Example #1 Writing to shared memory block

<?php
$shm_bytes_written 
shmop_write($shm_id$my_string0);
?>

This example will write data inside $my_string into shared memory block, $shm_bytes_written will contain the number of bytes written.

See Also

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User Contributed Notes 1 note

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radupb at yahoo dot com
4 days ago
I guess pack-unpack are the handy functions for encoding/decoding data as/from a binary string for shmop_write/shmop_read. Example:

$format='LLLLSSCCCC';  //data format for pack
$key=1;
if( !($shmid=shmop_open($key,'n',0660,30)) )
  die('shmop_open failed.');

//my data to encode:
$hd=array('ALIVE1'=>1,'ALIVE2'=>2,'ALIVE3'=>3,'ALIVE4'=>4,
      'CRTPTR'=>5,'CRTSEQ'=>6,
      'CTW'=>7,'LOCK'=>8,'PLAY'=>9,'MISS'=>10
);

$tmp=pack( $format, $hd['ALIVE1'],$hd['ALIVE2'],$hd['ALIVE3'],$hd['ALIVE4'],  $hd['CRTPTR'],$hd['CRTSEQ'],$hd['CTW'],$hd['LOCK'],$hd['PLAY'],$hd['MISS'] );

if( ($w=shmop_write($shmid,$tmp,0))!=24 )
  die('write error $w='.$w);

And reading from some other process:
$key=1;
if( !($shmid=shmop_open($key,'w',0,0)) )
  die('shmop_open failed.');

$formatR='L4ALIVE/SCRTPTR/SCRTSEQ/CCTW/CLOCK/CPLAY/CMISS'; //data format for unpack

$hd=unpack( $formatR, shmop_read( $shmid,0,24) );
echo'hd:<pre>';print_r($hd);echo'</pre>';
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