MATLAB Programming

Accessing Files with Memory-Mapping
Running the Demo
Here is what the demonstration looks like when it is run. First, start two
separate MATLAB sessions on the same computer system. Call the send
function in one and the answer function in the other to create a map in each of
the processes’ memory to the common file:
% Run SEND in the first MATLAB session.
send
Enter send string (or RETURN to end):
% Run ANSWER in the second MATLAB session.
answer
ANSWER server is awaiting message
Next, enter a message at the prompt displayed by the send function. MATLAB
writes the message to the shared file. The second MATLAB session, running
the answer function, loops on byte 1 of the shared file and, when the byte is
written by send, answer readsthemessagefromthefileviaitsmemorymap.
The answer function then puts the message into uppercase and writes it back
to the file, and send (waiting for a reply) reads the message and displays it:
% SEND writes a message and reads the uppercase reply.
Hello. Is there anybody out there?
response from ANSWER is:
HELLO. IS THERE ANYBODY OUT THERE?
Enter send string (or RETURN to end):
% ANSWER reads the message from SEND.
Received message from SEND:
Hello. Is there anybody out there?
send writes a second message to the file. answer readsit,putitinto
uppercase, and then writes the message to the file:
% SEND writes a second message to the shared file.
I received your reply.
response from ANSWER is:
I RECEIVED YOUR REPLY.
Enter send string (or RETURN to end):
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