对生产者-消费者问题的生产进程描述如下:producer(){while(1){wait(empty);wait( );buffer[in]=m;in=(in+1)%n;signal( );signal(full);}}
A. mutex
B. empty
C. full
D. null
在直接通信方式中,系统通常提供了两条通信原语,如下:send(__,message);receive(__,message);
A. sender , receiver
B. receiver , sender
C. sender ,sender
D. receiver ,receiver