‍Team members: Andrii Yaroshevych, Pavlo Krynenko

Description

This is a simple implementation of the cat utility. It is used to concatenate files and print on the standard output. The goal of this lab is to learn how to work with system calls and file descriptors.

Prerequisites

This project is written in C and doesn't use any third-party libraries. So, you need to have only:

C compiler (gcc, clang, etc.)
CMake 3.15 or higher
Make

Compilation

Using CMake directly

mkdir build

cmake -S . -B build -DCMAKE_BUILD_TYPE=Release && cmake --build build

Using `compile.sh` script

./compile.sh -O

Usage

mycat [-h|--help] [-A] <file1> <file2> ... <fileN>

For example:

./mycat README.md

Options

Option	Description
`-h`, `--help`	Print help message and exit
`-A`	Print all characters, including non-printable ones as `\xNN`
`<file1> <file2> ... <fileN>`	Files to concatenate

‍Note

If any of provided files cannot be opened, the program will exit with code 4 without printing any output.

Exit codes

Code	Description
1	Unknown option provided
2	No input files provided
3	Memory allocation error
4	Error opening file
5	Error getting file status
6	Error reading from file
7	Error writing to stdout

Results

My implementation of cat utility is working around 7% faster than the original one.

❯ ./mycat 10g_zero | pv > /dev/null
9.77GiB 0:00:17 [ 570MiB/s]
❯ cat 10g_zero | pv > /dev/null
9.77GiB 0:00:18 [ 532MiB/s]

Additional tasks

None of the additional tasks were implemented.