what is the “attribute” of a pthread mutex?

Question

The function pthread_mutex_init allows you to specify a pointer to an attribute. But I have yet to find a good explanation of what pthread attributes are. I have always just

Answer 1

Applying NULL to this argument implies using the default argument. So for some reasons you could want to change these default settings (using pthread_mutexattr_init).

The documentation explains all you need about these mutex settings.