下列关于进程间通信的描述中，不正确的是( )。A．进程互斥是指每次只允许一个进程使用
题型：单项选择题
问题：
下列关于进程间通信的描述中，不正确的是( )。
A．进程互斥是指每次只允许一个进程使用临界资源
B．进程控制是通过原语实现的
C．P、V操作是一种进程同步机制
D．管程是一种进程高级通信机制
题型：单项选择题
| 完形填空 | |||
| All the world asks On my first day in a college classroom,I felt like an overgrown child returning to civilization (文明世界) after having been lost in the forest for thirty years.There I sat,__1__enough to be a father to most of the students in the room,__2__unconfident enough to be their baby brother. We were crowded elbow (肘部) to elbow,listening to a__3__ who looked even younger than the students.I felt uncomfortable and out of place as the professor carefully__4__what she expected us to learn.As I listened,I couldn't help but__5__of my own oldest daughter who was now beginning her first year in__6  __,just like me.I rememberedhow hard I had tried to help build self－confidence in her and my other children.So why did I suddenly feel like a scared__7__myself?When I walked out of that classroom,I had serious __8__about my ability to make it__9__college. Not until late that night did my thinking__10__.It was a long－distance__11__from my daughter,my fellow college freshman (新生),that did the trick.She spoke on the phone about the doubts,worries and anxieties she was__12__.She was certain that she'd never__13__at college.How__14__her worries sounded.In my most confident parental__15__,I said,"Doing your best is all the world__16__"．The next day in class,those words still repeated in my head. When the professor raised a__17__for the class,nobody,including me,__18__to answer.When I looked around at the__19__and uncertainty on the young faces in that room,I knew__20__what I had to do:my best.That's all the world asks.So raised my hand,and the professor called my name. I spoke. | |||
| ( )1.A.big ( )2.A.and ( )3.A.professor ( )4.A.showed ( )5.A.think ( )6.A.school ( )7.A.father ( )8.A.fears ( )9.A.over ( )10.A.stop ( )11.A.call ( )12.A.obtaining ( )13.A.fail ( )14.A.common ( )15.A.sound ( )16.A.hopes ( )17.A.request ( )18.A.dared ( )19.A.sorrow ( )20.A.exactly | B．tall B．so B．teacher B．explained B．speak B．office B．parent B．doubts B．on B．turn B．talk B．gaining B．succeed B．ordinary B．whisper B．asks B．problem B．preferred B．joy B．roughly | C．old C．or C．lecturer C．designed C．talk C．classroom C．child C．opinions C．with C．change C．report C．experiencing C．win C．regular C．word C．wants C．question C．tried C．fear C．gradually | D．strong D．yet D．instructor D．offered D．hear D．college D．son D．ideas D．through D．continue D．discussion D．feeling D．pass D．familiar D．voice D．expects D．demand D．prepared D．anger D．certainly |