SDL Condition variables.

I find condition variables kind of strange because my SDL book (Focus on SDL, by Ernest Pazera) states that condition variables doesn't hold any value at all. How do they work then? Any good ideas?

To make my question more clear what happens when I signal a condition variable (to a waiting thread) if they can't hold a value?

No idea what you mean. Post some code.

Do you mean a condition statement?
eg

Code:

---

if( i == 10)

---

i is not assigned 10 is is only compared to it, resulting in true or false.

you mean an SDL_cond?

Code:

---

struct SDL_cond
{
        SDL_mutex *lock;
        int waiting;
        int signals;
        SDL_sem *wait_sem;
        SDL_sem *wait_done;
};

---

Holds multiple values.

Yes SDL_cond is exactly what I mean, but now I really do not understand why the book tells me that it doesn't hold any values since it seem to hold more than one... anyway thanks for your help I'll just ignore what that line in the book suggested. It just sounded stupid with a struct that would never hold a value.