Synchronized access to shared memory

Synchronized access to shared memory

Post by Constantine Knizhni » Sat, 25 Apr 1998 04:00:00



Dear developers

I like to anonce a class library providing effective and operating system
independent interface to shared memory. This class makes it possible for
several applications to access objects in shared memory. Methods
for allocation/deallocation of objects in shared memory, setting exclusive
or shared locks are available. Locks can be nested and can be used to
synchronize access
to shared objects by different threads within process as well as
by different processes.

Locking is based on atomic instructions of i486 (and higher) processors XADD
and CMPXCHG.
So no context switching are required to lock storage in most common case,
when no other processes are  working with the storage. That is why overhead
of locking is minimal.

In addition to the storage locking mechanism,  there are two other
synchronization primitives:
"semaphore" and "event", providing system independent and convenient
interface for interprocess
communication.

There is also implementation of Posix semaphores for Linux based in IPC
semaphores.
Also interface of semaphores located in shared memory is provided.

This library can be used under Windows NT/95 as well as at Unix's for i86
platform with GCC (currently tested only for Linux). It can be downloaded
from my homepage:

http:/www.ispras.ru/~knizhnik

 
 
 

Synchronized access to shared memory

Post by Greg Herlei » Sat, 25 Apr 1998 04:00:00



> http:/www.ispras.ru/~knizhnik

looks interesting but ny DNS does not recognize you.  Is there a typo

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Synchronized access to shared memory

Post by Constantine Knizhni » Tue, 28 Apr 1998 04:00:00


Please try
http://194.67.37.200/~knizhnik



>> http:/www.ispras.ru/~knizhnik

>looks interesting but ny DNS does not recognize you.  Is there a typo

 
 
 

1. Synchronizing Shared Memory access

My initial requirement is to have two independent processes where one
process writes into the shared memory and the other process reads from
it. Now this Write and Read should be synchronised using
Semaphores(I've to use System V semaphores).
So any information on how to implement this would be welcome, OR any
example Source Code will also be of great help.

Thanks in advance......

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