Exercises

   


10.1 What are the two general modes of terminal input? Which mode is most commonly in use when users converse with an interactive screen editor?

10.2 Explain why there are two character queues for dealing with terminal input. Describe the use of each.

10.3 What do we mean when we say that modem control is supported on a terminal line? How are terminal lines of this sort typically used?

10.4 What signal is sent to what process associated with a terminal if a user disconnects the modem line in the middle of a session?

10.5 Name the two devices that make up a pseudo-terminal. Explain the role of each of these pieces.

10.6 How is the high watermark on a terminal's output queue determined?

*10.7 Consider a facility that allowed a tutor on one terminal to monitor and assist students working on other terminals. Everything the students typed would be transmitted both to the system as input and to the tutor's terminal as output. Everything the tutor typed would be directed to the students' terminals as input. Describe how this facility might be implemented with a special-purpose line discipline. Describe further useful generalizations of this facility.

*10.8 The terminal line discipline supports logical erasure of input text when characters, words, and lines are erased. Remembering that other system activities continue while a user types an input line, explain what complications must be considered in the implementation of this feature. Name three exceptional cases, and describe their effects on the implementation.

**10.9 Propose another buffering scheme to replace C-lists.


   
 


The Design and Implementation of the FreeBSD Operating System
The Design and Implementation of the FreeBSD Operating System
ISBN: 0201702452
EAN: 2147483647
Year: 2003
Pages: 183

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