if you are using shared data, use mutexes for both reading and writing. Surround your read and write sections with pthread_mutex_lock() and pthread_mutex_unlock(), or use them any time a program's invariant is temporarily broken.

"dead list" that contains all stopped threads and then have a special cleanup thread that simply waits for an item to be added to the list. The cleanup thread calls pthread_join() to merge it with itself. Now your entire cleanup will be handled neatly and efficiently in a single thread.

mutexes are used to serialize access to *shared data*. Don't use them for non-shared data, and don't use them if your program's logic ensures that only one thread is accessing a particular data structure at a single time.

pthread_mutex_destroy() does not free the memory used to store the pthread_mutex_t. It's up to you to free() your own memory. Also remember that both pthread_mutex_init() and pthread_mutex_destroy() return zero on success.

pthread_mutex_lock() accepts a single pointer to a mutex to lock. If the mutex already happens to be locked, the caller will go to sleep. When the function returns, the caller will be woken up (obviously), and the caller will also now hold the lock. This call either returns zero on success.

You should always unlock a mutex that you've locked as soon as safely possible (to increase performance). And you should never unlock a mutex that you don't hold a lock for

When you call pthread_mutex_trylock() you'll attempt to lock the mutex. If the mutex is currently unlocked you'll get the lock, and this function will return zero. However, if the mutex is locked this call won't block. Rather, it will return a non-zero EBUSY error value.

pthread_cond_wait() simultaneously unlock the mutex (so that other threads can modify the linked list) and wait on the condition (so that pthread_cond_wait() will wake up when it is "signalled" by another thread). Now that the mutex is unlocked, other threads can access and modify the linked list, possibly adding items

pthread_cond_wait() call has not yet returned. Unlocking the mutex happens immediately, but waiting on the condition mycond is normally a blocking operation, meaning that our thread will go to sleep, consuming no CPU cycles until it is woken up.

This is exactly what we want to happen. Our thread is sleeping, waiting for a particular condition to become true, without performing any kind of busy polling that would waste CPU time. From our thread's perspective, it's simply waiting for the pthread_cond_wait() call to return.

Immediately after unlocking the mutex, thread 2 calls the function pthread_cond_broadcast(&mycond). By doing so, thread 2 will cause all threads waiting on the mycond condition variable to immediately wake up. This means that our first thread (which is in the middle of a pthread_cond_wait() call) will now wake up.

After thread 2 called pthread_cond_broadcast(&mymutex) you might think that thread 1's pthread_cond_wait() will immediately return. Not so! Instead, pthread_cond_wait() will perform one last operation: relock mymutex. Once pthread_cond_wait() has the lock, it will then return and allow thread 1 to continue execution.

There is no free speech in football. Information is parsed by monosyllabic head coaches, who dictate who gets to speak to whom and when.

Let me tell you I am better acquainted with you for a long absence, as men are with themselves for a long affliction: absence does but hold off a friend, to make one see him the truer.

I know now that everything I write, I'm going to put out, and I'll have to live with it for the rest of my life.

I wanted to be cast because I'm an actor and not because of how I look or where I'm from. I'm brown. I want to be able to play a Spanish girl some day or a Mexican girl and learn the language. That's what actors do: we act.

Contentment consists not in adding more fuel, but in taking away some fire; not in multiplying of wealth, but in subtracting people's desires. Generally those who boast most of contentment have least of it. Their very boasting shows they want something and basely beg it, namely commendation.

I realized that I was afraid to really, really try something, 100%, because I had never reached true failure.

I came to L.A. in 1970, and my desire and my training was to be a studio musician, which I had read about in my senior year in high school.

It's a lonesome walk to the sidelines, especially when thousands of people are cheering your replacement.

I believe in Christianity as I believe that the sun has risen. Not only because I see it but because I see everything by it.

The media has changed. We now give broadcast licenses to philosophies instead of people. People get confused and think there is no difference between news and entertainment. People who project themselves as journalists on television don't know the first thing about journalism. They are just there stirring up a hockey game.

We all suffer from dreams.

Tolerance it a tremendous virtue, but the immediate neighbors of tolerance are apathy and weakness.

I have trouble with seafood because it tastes like a dock.

I want to touch the heart of the world and make it smile.

When I was a child, I saw my father diving to the deepest point in the ocean with the U.S. Navy.

We're helping those children who cannot help themselves and giving a push to those who can. We've done it by working together for a common purpose. I see no reason to stop now.

I've always been rapping before I was making money off of it. Before I made a profit, I had always been rapping.

I give all the glory to God. Its kind of a win win situation. The glory goes up to Him and the blessings fall down on me.

I would encourage more development in the boroughs outside of Manhattan as well. I think it's great that this natural emergence has occurred in the lower part of Midtown, but there's tremendous potential in Brooklyn, Queens, the Bronx, and Staten Island as well.

Conspiracy is just another name for coalition.

Nerves are good. They keep you alive.

When I was to come to Washington the first time as Music Director of the Boston Symphony, Mrs. Johnson phoned us to find out if they could give us a party and who we would like to meet.

I've been absolutely terrified every moment of my life - and I've never let it keep me from doing a single thing I wanted to do.

There is no person that love cannot heal; there is no soul that love cannot save.