CS360 Final Exam: December 12, 2000. Question 3
Write a program called server, which does the following:
- It serves a socket on hydra3a.cs.utk.edu, port 5678.
- It accepts connections from clients that will use telnet.
- It maintains a count of the number of clients that are currently
attached to the server.
- Whenever a client attaches to the server, the server sends the
client its count.
- Otherwise, it ignores any input from its clients, and does not
send clients any output.
- Note, when a client detaches from the server,
the server needs to update its count.
Implement this using pthreads. You may use global variables if you
want. I don't care, and it will make your life easier.
Also, you may use the routines from jthread.h if you would
like.
Make sure your program does not perform poorly if there are bad
network connections, and do not make an inordinate number of
system calls if you do not have to. Do not worry about handling
SIGPIPE.
CS360 Final Exam: December 12, 2000. Question 4
Part i: Why did I say to use the routines
from jthread.c in Question 3?
Part ii: Precisely define the semantics of the two functions:
int pthread_cond_wait(pthread_cond_t *cv, pthread_mutex_t *lock);
int pthread_cond_signal(pthread_cond_t *cv);
CS360 Final Exam: December 12, 2000. Question 5
Write a program called shc.c, which does exactly what the
shell does when it executes:
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sort < f1 | head -5 | cat -n
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You must do your answer on the answer sheet provided,
because it fills in some of the code for you.
If you start and mess up, take another answer sheet. I have
made at least two copies for each person.