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.

"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.

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.

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

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.

Writings a lot like cooking. Sometimes the cake wont rise no matter what you do and every now and again the cake tastes better than you ever could have dreamed it would.

As Republicans, our challenge is to become a pro-market party and not be a pro-business party.

And it was at that point that I realized, in fact, our whole administration realized, that we could not rely on Metropolitan Edison for the kind of information we needed to make decisions.

Growing up, I was such a picky eater. I'm finally starting to expand.

There is no job that is America's God-given right anymore.

Real emotion is good or doing a good job of faking real emotion.

I played crying people in corsets for a long time, but I went into acting to be a character actor.

The funny thing is, people only know me for having straight hair for work, but I live in Atlanta where it's hot and humid in the summertime. So when I'm home, I wear my hair natural. My hair is naturally curly; I don't have a relaxer.

You cannot teach creativity - how to become a good writer. But you can help a young writer discover within himself what kind of writer he would like to be.

No one cares how valuable your product is if its addressable market is small. The key isn't so much the number of users as it is the dollar size of the market.

The only meal I have is dinner.

Sure, one can always get the students to relax and be happy - entertained, but although being laid back and relax can also lead to creativity, mostly it means that nothing much gets done.

Time destroys everything.

When I first got into wrestling as a kid, I would read all of the wrestling magazines I could get my hands on. There was a satisfaction discovering that there was a whole wrestling world that existed that you didn't see on TV on Saturday morning. There was this idea that there was this stuff going on there that they didn't want us to see.

I want to solidify as an artist and show that as I grow as a person and make mistakes and learn from them, I'm going to grow artistically.

When we started out doing YouTube videos, I think we were very, very early on in terms of people doing a behind-the-scenes component.

I was so lucky and blessed to have gotten 'White Chicks' so early into my career.

From a young age, I wanted to play in the NBA. Oh well... It was when I was a senior in college that I fell for film, but even then, it wasn't documentaries. It wasn't until I ended up in graduate school at Southern Illinois University that I really discovered documentaries and thought that maybe that would be my calling.

I've always been told I have a giant placenta.

Politics is not really my thing.

History is only the register of crimes and misfortunes.

If we have no respect for our viewers, then how can we have any respect for ourselves and what we do?

Africa is probably one of the most beautiful places I have ever been.

A figure skater is not just a figure skater who does great jumps. He is an artist on ice.