Re: Noob on memory and data streams...

Victor Bazarov <>
Fri, 08 May 2009 08:52:32 -0400
noemailplease wrote:

Victor Bazarov wrote:

noemailplease wrote:

I would like to write a (small) app in C++ that streams a "signal
value" (-1, 0 , +1) to a specific memory address where this value can
be read by a second application (over which I have very little
control, other than (possibly) specifying the memory address of the
signal values).

This all seems a bit long-winded in my mind, and raises several

Is it possible to specify (hard-code?) an address in which store a

That's platform-specific. There is no portable way.

How does one check that address is free beforehand?

Unknown. In most cases there is no way an application (a process) can
check anything that might belong to another application (process).
It's called "memory protection".

Is there some sort of semaphore to stop read/write collisions between
different applications?

There are ways to synchronize access to a resource. They are
platform-specific in most cases.

Is there a better way to do this?



Hi Victor,
Thanks for taking the time to respond.

Would a pipe help me in this case?

Unknown (from the C++ point of view). C++ does not have any definition
of "pipe". You'll need to ask in the newsgroup for your OS.

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