(PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)
shmop_read — Read data from shared memory block
shmop_read() will read a string from shared memory block.
shmopThe shared memory block identifier created by shmop_open()
offsetOffset from which to start reading; must be greater than or equal to zero and less than or equal to the actual size of the shared memory segment.
size
The number of bytes to read; must be greater than or equal to zero,
and the sum of offset and size
must be less than or equal to the actual size of the shared memory segment.
0 reads shmop_size($shmid) - $start bytes.
Returns the data or false on failure.
If offset or size are out of range,
a ValueError is thrown.
| Version | Description |
|---|---|
| 8.0.0 |
shmop expects a Shmop
instance now; previously, a resource was expected.
|
| 8.0.0 |
If offset or size are out of range,
a ValueError is thrown; previously E_WARNING
was emitted, and false was returned,
|
Example #1 Reading shared memory block
<?php
$shm_data = shmop_read($shm_id, 0, 50);
?>
This example will read 50 bytes from shared memory block and place the data
inside $shm_data.