IPC::SharedMem - SysV Shared Memory IPC object class
use IPC::SysV qw(IPC_PRIVATE S_IRUSR S_IWUSR);
$shm = IPC::SharedMem->new(IPC_PRIVATE, 8, S_IRWXU);
$shm->write(pack("S", 4711), 2, 2);
$data = $shm->read(0, 2);
$ds = $shm->stat;
A class providing an object based interface to SysV IPC shared memory.
Creates a new shared memory segment of SIZE bytes size associated with KEY. A new segment is created if
KEY is equal to IPC_PRIVATE
KEY does not already have a shared memory segment associated with it, and FLAGS & IPC_CREAT is true.
FLAGS & IPC_CREAT
On creation of a new shared memory segment FLAGS is used to set the permissions. Be careful not to set any flags that the Sys V IPC implementation does not allow: in some systems setting execute bits makes the operations fail.
Returns the shared memory identifier.
Read SIZE bytes from the shared memory segment at POS. Returns the string read, or undef if there was an error. The return value becomes tainted. See shmread.
Write SIZE bytes to the shared memory segment at POS. Returns true if successful, or false if there is an error. See shmwrite.
Remove the shared memory segment from the system or mark it as removed as long as any processes are still attached to it.
Returns true if the shared memory segment has been removed or marked for removal.
Returns an object of type IPC::SharedMem::stat which is a sub-class of Class::Struct. It provides the following fields. For a description of these fields see you system documentation.
Permanently attach to the shared memory segment. When a IPC::SharedMem object is attached, it will use memread and memwrite instead of shmread and shmwrite for accessing the shared memory segment. Returns true if successful, or false on error. See shmat(2).
Detach from the shared memory segment that previously has been attached to. Returns true if successful, or false on error. See shmdt(2).
Returns the address of the shared memory that has been attached to in a format suitable for use with pack('P'). Returns undef if the shared memory has not been attached.
Marcus Holland-Moritz <email@example.com>
Version 2.x, Copyright (C) 2007-2013, Marcus Holland-Moritz.
Version 1.x, Copyright (c) 1997, Graham Barr.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
To install IPC::SysV, copy and paste the appropriate command in to your terminal.
perl -MCPAN -e shell
For more information on module installation, please visit the detailed CPAN module installation guide.