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Examples/pthreads/README.md

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+# pthread examples
+
+CS3841 examples using the pthread library to create POSIX threads
+
+* pthreads1.c - Shows how to create and wait for single thread (beyond the main thread)
+
+* pthreads2.c - Shows how to create and wait for multple threads (beyond the main thread)  
+Threads prints out its thread ID and process ID  
+Shows that threads share the same process ID but all have their own thread ID
+
+* pthreads3.c - Shows how to pass parameter values to thread routines
+
+* pthreads4.c - Shows how to pass parameter values to thread routines  
+The threads dereference the pointer passed to the thread routine to demonstrate that memory is shared between all threads
+
+* pthreads5.c - Shows a problem that can happen with parameters passed to thread routines due to the fact that the parameter must be a pointer  
+The referenced location must be valid for the entire life of the thread  
+NOTE: Context switches between threads can happen when unexpected
+
+* pthreads6.c - Shows the problems that can happen due to the fact that thread routine parameters are pointers to memory locations  
+Threads can easily affect other threads memory  
+NOTE: Context switches between threads can happen when unexpected
+
+* pthreads\_race.c - Shows a "race condition" when multiple threads try to race to modify a global value  
+Due to unpredictable behavior in context switching the value of global\_value does not result in what is expected
+
+* pthreads\_race\_atomic.c - Uses an atomic add instruction to prevent the race condition that can happen when multiple threads modify a global value at the same time