About creating entry points in C++
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About creating entry points in C++

Because the agent framework is multithreaded, all C++ code written by the agent developer must be MT-safe. For best results, avoid using global variables. If you do use them, access must be serialized (for example, by using mutex locks).

The following guidelines also apply:

• Do not use C library functions that are unsafe in multithreaded applications. Instead, use the equivalent reentrant versions, such as readdir_r() instead of readdir(). Access manual pages for either of these commands by entering: man command.
• When acquiring resources (dynamically allocating memory or opening a file, for example), use thread-cancellation handlers to ensure that resources are freed properly. See the manual pages for pthread_cleanup_push and pthread_cleanup_pop for details. Access manual pages for either of these commands by entering: man command.

If you develop an agent with at least one entry point implemented in C++, you must implement the function VCSAgStartup() and use the required C++ primitives to register the C++ entry point with the agent framework.

A sample file containing templates for creating an agent using C++ entry points is located in:

UNIX: $VCS_HOME/src/agent/Sample

You can use C++ to develop agents for monitoring applications that run in containers, including non-global zones. VCS provides APIs for container suppport.

See Agent Framework primitives for container support.