Description
Section 2.3 (Figure 2.4) of our textbook describes an algorithm for implementing a
COPY program. This program prompts the user for the input and output file names,
then copies the contents of the input file to the output file. You will be
implementing this pseudocode. The standard tee command copies data from
standard input to standard output (like an ordinary shell pipe), however it also
writes a copy of standard input to a file named on the command line. See the man
page for details. Your program’s user interface should appear exactly asfollows:
Welcome to the File Copy Program by !
Enter the name of the file to copy from:
Enter the name of the file to copy to:
File Copy Successful, bytes copied
You will implement this program in the C language (gcc compiler) using the POSIX
(i.e. Linux) API/gcc compiler. Your code should use a buffer of size 27 bytes.
Following the pseudocode logic, the file read will repeatedly read from the input
file into the buffer, and the file write will repeatedly write from the buffer to the
output file.
For the Linux implementation, use the low-level file I/O API for reading/writing the
files (this API is also referred to as the OPEN family of Linux system calls); use the
FORMATTED I/O API for prompting the user and reading user input (this API is also
referred to as the FOPEN family of system calls). Be sure to include all necessary
error checking, including ensuring that the source file exists and the destination file
does not exist (before opening it). Use the man page entries for function prototypes,
details on how to use each system call as well as all of the necessary #include files.
Note that most system calls are in section 2 or 3 of the man pages (i.e. use ‘man 2
write’ not ‘man write’ to get information about the write system call).
1. Implement your program and test it for correct implementation using three
(small) test files. Use the Linux diff utility to compare your input and output
files. Also instrument your program with debugging code to display the
buffer contents during each file read/write iteration. Include debugging
output for a small test file; and also test your program using 3 larger files
(without debugging output). Once you have correctly designed and tested
your program, run the program using the strace utility that traces (lists) all
of the system calls used during execution. Explain (annotate) this output. Do
your best to explain this output. This explanation should be writing in your
readme.txt file. Set the strace flags to display the number of times each
syscall is used in your program.
Homework Submission
1. A readme.txt file which contains the following:
• The command to build your project.
• The command to run your project.
• What your code does.
• Annotated output of strace of your program.
2. Push all files to your repository with the following commands
• git add .
• git commit -m “message”
• git push
