Debugging Memory Problems with MemoryScape : Chapter 2 Memory Tasks : Task 1: Getting Started : Attaching to Programs and Adding Core Files
Attaching to Programs and Adding Core Files
If you wish to attach to a program that is already running or a core file, click either the Attach to running program or Add core file link on the Add Programs to Your MemoryScape Session page.
Within the Attach to a Running Program screen, select the processes you would like to attach to, then click the Next button. Adding a core file is done in exactly the same way as a regular program except that you need to name the location of the core file and the executable.
 
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MemoryScape requires that all programs use the MemoryScape agent. In most cases, it does this behind the scenes for you before the program begins executing. It cannot do this for an already executing program or for a core file. So, just attaching to an already running program will not provide the information you need as the agent isn’t being used with your program. In some cases, you may want to add it by starting the program using the shell env command. However, the best alternative is to link the MemoryScape agent. For details, see Linking Your Application with the Agent”.