pthread_mutex_t pthread_mutex_init pthread_mutex_lock -- pthread_mutex_unlock pthread_delay_np

void reader_function ( void );
void writer_function ( void );

char buffer;
int buffer_has_item=0;
pthread_mutex_t mutex;
struct timespec delay;
void main ( void ){
　pthread_t reader;
　/* 定义延迟时间*/
　delay.tv_sec = 2;
　delay.tv_nec = 0;
　/* 用默认属性初始化一个互斥锁对象*/
　pthread_mutex_init (&mutex,NULL);
　pthread_create(&reader, pthread_attr_default, (void *)&reader_function), NULL);
　writer_function( );
}

void writer_function (void){
　while(1){
　　/* 锁定互斥锁*/
　　pthread_mutex_lock (&mutex);
　　if (buffer_has_item==0){
　　　buffer=make_new_item( );
　　　buffer_has_item=1;
　　}
　　/* 打开互斥锁*/
　　pthread_mutex_unlock(&mutex);
　　pthread_delay_np(&delay);
　}
}

void reader_function(void){
　while(1){
　　pthread_mutex_lock(&mutex);
　　if(buffer_has_item==1){
　　　consume_item(buffer);
　　　buffer_has_item=0;
　　}
　　pthread_mutex_unlock(&mutex);
　　pthread_delay_np(&delay);
　}
}