Solved

Shared Memory and inheritance

Posted on 1998-03-27
1
209 Views
Last Modified: 2013-12-03
I am currently using CreateFileMapping() and MapViewOfFile() to create a block of shared memory using 0xFFFFFFFF as the first parameter of the CreatFileMapping() call so its not associated with a file but uses the system paging file.



However, by giving it a name "MY_SHARED_MEM", so both processes will attach to the same area, this leaves me with a problem.



At some point in time, these applications may run on an NT server and so there may be multiple processes running. I only want the main process and the child process *of that main process* to access the shared memory. As it is, I 'think' that if another uses starts a 2nd main process and launches the child, they will attach to the original area, becuase of the name correct?



How can I avoid this, and yet still use the system paging file? . use the CreateProcess to launch the child with handle inheritance set to TRUE if thats necessary to do this. I've read about DuplicateHandle() but not sure how to set it up..can't quite get a grasp on it.



Any help would be appreciated
0
Comment
Question by:gunn
1 Comment
 
LVL 15

Accepted Solution

by:
Tommy Hui earned 110 total points
ID: 1412338
This is not that unusual. One idea is to not hardcode a specific name, but to use one based off of the processId of the parent. For example, instead of using MY_SHARED_MEM as the name of the filemap, use MY_SHARED_MEM_%PROCESSID%. Then when the parent process launches the child, pass the child the name as an argument.

0

Featured Post

Salesforce Has Never Been Easier

Improve and reinforce salesforce training & adoption using WalkMe's digital adoption platform. Start saving on costly employee training by creating fast intuitive Walk-Thrus for Salesforce. Claim your Free Account Now

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

This tutorial is about how to put some of your C++ program's functionality into a standard DLL, and how to make working with the EXE and the DLL simple and seamless.   We'll be using Microsoft Visual Studio 2008 and we will cut out the noise; that i…
In this article, I will show how to use the Ribbon IDs Tool Window to assign the built-in Office icons to a ribbon button.  This tool will help us to find the OfficeImageId that corresponds to our desired built-in Office icon. The tool is part of…
This is Part 3 in a 3-part series on Experts Exchange to discuss error handling in VBA code written for Excel. Part 1 of this series discussed basic error handling code using VBA. http://www.experts-exchange.com/videos/1478/Excel-Error-Handlin…
In a recent question (https://www.experts-exchange.com/questions/29004105/Run-AutoHotkey-script-directly-from-Notepad.html) here at Experts Exchange, a member asked how to run an AutoHotkey script (.AHK) directly from Notepad++ (aka NPP). This video…

730 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question