NEED HELP ASAP C++ PROGRAMMING

PLEASE SOLVE AND GIVE SOME COMMENTS TO HELP MYSELFUNDERSTAND THE PROGRAM ASSIGNMENT PLEASE AND THANK YOU

One of the many command-line utilities available on Linux (and other Unix-like

systems) is cat, which is short for concatenate. In its simplest form, cat can

display the contents of a text file; it can also be used to concatenate together

many text files.

For this assignment, you are going to write your own version of cat.

Before you proceed, you should first play with cat on the command line. Get

into your Docker environment (or alternative, for those of you using Virtualbox

or CodeAnywhere or another solution).

Type cat /etc/hosts and notice that the contents of the file /etc/hosts

are printed out.

Now, type cat /etc/hosts /etc/hosts and see if you can make sense of

the output.

Now, try typing cat /etc/hosts /etc/hosts > test.txt

Followed by cat test.txt.

How do the contents of test.txt compare with the output of cat

/etc/hosts /etc/hosts?

As an aside, the > redirected the output from cat to the new file

test.txt.

What cat does is that it takes one or more filenames as command-line arguments.

It prints out the contents of each file in turn. By using the Unix shell feature

of redirection (the > character), we can combine all of those files into one file.

Undoubtedly, you can imagine circumstances when this would be useful.

So, your cat must do the same. Like the echo program you wrote for Lab 2,

cat takes several command line arguments. But, it must try to open a file with

the same name as each command-line argument. If it cant open a file, it must

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print could not open file to the special output stream STDERR followed by the

name of the offending file.

Submission limits

For this assignment, you only get 5 submissions to Mimir, so make sure to

test locally first. Only submit to Mimir when you have successfully run your

program locally on several different inputs (including on files that dont exist).

Academic honesty

Remember, this is a solo assignment. You may not show your code to any

classmate, or look at any classmates code.

Getting Started

Get into your Docker development environment (or appropriate alternative,

such as CodeAnywhere.com)

Download the assignment framework with git clone https://github.com/csc211/a3

You will see this Readme.md along with a C++ source file (cat.cpp) and

a compile script compile

You can now compile the assignment by typing ./compile and it will

produce an executable program called cat. You can run cat by typing

./cat However, it wont do anything yet!

Read the existing comments in cat.cpp carefully and be sure you understand

them before doing anything else!

Requirements

Your program must take one or more command-line arguments, each of which

should be a file name. It must print out the contents of each file in the order

given by the command-line arguments. If any file specified cannot be opened, the

message cat: followed by the filename, followed by : no such file or directory

must be printed to STDERR. Note that just as std::cout << "hi" prints the

message hi to STDOUT, std::cerr << "hi" prints it to STDERR. The difference

between these different output streams will be discussed in class.

If given no command-line arguments, your program should simply exit (your

main() can issue a return 0).

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Comments

Your comments should explain the contract of any function you write.

That is what arguments does a function expect, and what value does it return,

and what is the relationship between the two.

Comments should not focus on explaining the C++ language to the reader,

though at this point, if doing so helps you understand your own code, its fine.

Any code you write that you think is particularly clever should be explained

(for example, non-obvious corrections for off-by-one errors, or a for loop that

starts at an index other than 0).

Hints

We have seen two approaches to read from a file. The first is character-oriented

input:

stream.get() stream.put()

ifstream infile(filename);

char ch;

while (infile.get(ch)) {

cout << ch;

}

infile.close()

The second is line-oriented input

getline(stream, str)

Note that this is a bare function, rather than a method on the ifstream class.

ifstream infile;

infile.open(filename);

std::string line;

while (getline(infile, line)) {

std::cout << line << std::endl;

}

infile.close();

Testing your own code

One benefit to reimplementing a common program like cat is that you can test

your program side-by-side with cat to make sure the output is the same.

Type cat compile. What do you see?

Type cat compile compile. Now, what do you see?

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Type cat compile nothing. Assuming there is no file called nothing in

your project directory, whats going on?

Now, if your program is working, running the same commands with your

own cat program should produce the same output:

Type ./compile to compile your program.

Type ./cat compile to run your own cat program. Does your program

behave the same as the built-in cat command?

Try it with other inputs, and make sure it behaves the same. Once it does,

you should submit it to Mimir.

Note that you have limited submissions on Mimir, so you must test locally

(in Docker or CodeAnywhere or Virtualbox, or whatever alternative you

have set up).