This utility allows you to see the contents of a shared memory segment created using the shm_* functions in PHP. Unlike the shmop functions, which allow you to read and write raw data in a shared memory segment, these are designed for PHP only and consist of serialized PHP variables in a linked list.
As there is no way to enumerate the values in a shared memory segment, this utility uses the shmop functions to read the segment raw, and then parses the data according to the sysvshm_chunk_head and sysvshm_chunk PHP-internal structures.
Usage: getshm [-v] <shmkey> -v verbose information (byte pointers, etc) <shmkey> shared memory key passed to shm_attach()
-v gives you all the pointers and lengths from the raw shared memory segment.
Note you will need read access to the segment; the mode used to create the segment will affect your ability to read the segment if are not the user who created the segment.
david@a6s:~# getshm 0x00120003 shm key 0x00120003 (1179651): Variable: Key: 0 Data: string(2) "aq" Variable: Key: 1 Data: int(201577)
david@a6s:~# getshm -v 0x00120003 shm key 0x00120003 (1179651): segment size: 500 Header: Magic: "PHP_SM" Data Start: 24 Data End: 80 Bytes Free: 420 Bytes Total: 500 Variable: Key: 0 Length: 9 Next: 28 Raw Data: "s:2:"aq";" Unserialized data: string(2) "aq" Variable: Key: 1 Length: 9 Next: 28 Raw Data: "i:201579;" Unserialized data: int(201579)
The sysvshm_ structures may change in a future version of PHP and cause this utility to break.
This is designed to read shm_* format segments only and will throw errors on other types of segment including raw shmop_* segments.
|getshm.php (2004-05-13 14:23)||2.05 KB|