2005-06W CSE3221 Assignment 2
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This assignment is due by 7:00 p.m. on Monday, March 13.
1. Write an ansi C (not C++) program called q1.c. It will be invoked with
4 arguments, as in
% q1 <max> <bufLength> <nProducers> <nConsumers>
The original process will
- create adequate shared memory space to hold a 2-D int array
of size 2 by <bufLength> plus any other space necessary.
- create <nProducers> children, which we'll call "producers".
The producers are numbered 1 ... <nProducers> and each producer
knows its own number.
- create <nConsumers> children, which we'll call "consumers".
The consumers are numbered 1 ... <nConsumers> and each consumer
knows its own number.
The producers will, between them, write the numbers 1 to <max>
inclusive to the buffer. More exactly, each producer number x will
do the following:
while there is a number n in 1 ... <max> that has not been written
to the buffer
- write to the buffer the pair (n, x)
- sleep a random time between 0 and 0.01 seconds
The consumers will, between them, read the numbers from the buffer
and write them to standard output. More exactly, each consumer y
will do the following
while not all numbers in 1 ... <max> have been output
- read the next pair (n, x) from the buffer, say from buffer
slot number i (buffer slots are numbered 0 .. <bufLength> - 1).
- write to standard output 4 values separated by single blanks
and followed by a newline character. That is, write
n x y i
- sleep a random time between 0 and 0.01 seconds
The original process will then write DONE (in upper case) followed by
a newline character to standard output.
You may wish to look at the man pages for shmget and semget and the
other system calls mentioned there.
2. Write an ansi C (not C++) program called q2.c. It will be invoked with
4 arguments, as in
% q2 <max> <bufLength> <nProducers> <nConsumers>
This program will function the same way as q1.c, except that, instead
using of shared memory and child processes it will create and use
posix threads. You may wish to look at the man pages for pthread_create,
pthread_mutex_init, pthread_cond_init and the other system calls mentioned
there.
Partners
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You can work in groups of up to 3.
Submissions
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There is no hardcopy submission. Submit electronically as follows:
Make a directory called Q1 and place all question 1 files in it
(i.e. q1.c, makefile and anything else you need).
This is a directory, not a .tar file. Make a directory called
Q2 and place all question 2 files in it. Submit with the command
% submit 3221 a2 Q1 Q2
The submitted files should start with the names, csLogins, student numbers
and sections of all partners who worked on the assignment. Only one
submission per group. Each submitted directory Qx should contain a
makefile (called "makefile") that produces the targets qx (i.e., the
executable q1 or q2), clean, doc and man, with the same specifications as
in assignment 1.
Programming Standards and Documentation
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As in assignment 1, you have to write high quality code with good error
checking, useful comments and graceful error handling. The return values
of all system calls that can return an er...