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copied!<p>I am wondering why it would be incorrect to implement this sort of queue the naive way:</p> <pre><code>#include <stdlib.h> #include <stdio.h> #include <pthread.h> #include <sys/time.h> void *print_message_function( void *ptr ); void *reader( void *ptr ); void *writer( void *ptr ); int queue[500000]; int main(int argc, char **argv) { pthread_t thread1, thread2; char *message1 = "Thread 1"; char *message2 = "Thread 2"; int iret1, iret2; iret1 = pthread_create( &thread1, NULL, writer, (void*) message1); iret2 = pthread_create( &thread2, NULL, reader, (void*) message2); usleep(2000); void pthread_exit(void *iret1 ); void pthread_exit(void *iret2 ); exit(0); } void *writer( void *ptr ) { // make local copy of queue head register int *pos = queue; // struct thread_param *tp = arg; int counter = 0; while(1) { //Write to head of queue *pos = 5; pos++; print_message_function( ptr); } } void *reader( void *ptr ) { int counter = 0; // make local copy of queue head register int *pos = queue; while(1) { // Read from tail of queue - loop when nothing if ( *pos == 5 ) { print_message_function( ptr ); pos++; } } } void *print_message_function( void *ptr ) { char *message; message = (char *) ptr; printf("%s \n", message); } </code></pre> <p>I do intend to cache align the queue. </p> <p>I do not believe memory reordering is a problem since a copy of the queue head is made on start and there is a single reader and writer. </p> <p>My reason for wanting this is it should be faster than either mutex locks or CAS ops.</p>

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