What are the "things to know" when diving into multi-threaded programming in C++

Question

I'm currently working on a wireless networking application in C++ and it's coming to a point where I'm going to want to multi-thread pieces of software under one process, rather than have them all in separate processes. Theoretically, I understand multi-threading, but I've yet to dive in practically.

What should every programmer know when writing multi-threaded code in C++?

Answer 1

I would focus on design the thing as much as partitioned as possible so you have the minimal amount of shared things across threads. If you make sure you don't have statics and other resources shared among threads (other than those that you would be sharing if you designed this with processes instead of threads) you would be fine.

Therefore, while yes, you have to have in mind concepts like locks, semaphores, etc, the best way to tackle this is to try to avoid them.

Answer 2

I am no expert at all in this subject. Just some rule of thumb:

1. Design for simplicity, bugs really are hard to find in concurrent code even in the simplest examples.
2. C++ offers you a very elegant paradigm to manage resources(mutex, semaphore,...): RAII. I observed that it is much easier to work with boost::thread than to work with POSIX threads.
3. Build your code as thread-safe. If you don't do so, your program could behave strangely