go-cat

A Go implementation of the Unix cat command with support for common flags.

Features

• Read and display file contents
• Support for multiple files
• Stream-based reading (memory efficient for large files)
• Command-line flags for enhanced output

Supported Flags

Flag	Description
-n	Number all lines
-b	Number non-empty lines only
-s	Squeeze consecutive blank lines into one
-E	Show end of line with $ character

Building

go build -o go-cat

Usage

Basic usage

./go-cat file.txt

Display multiple files

./go-cat file1.txt file2.txt file3.txt

Number all lines

./go-cat -n file.txt

Number non-empty lines

./go-cat -b file.txt

Squeeze blank lines

./go-cat -s file.txt

Show end of lines

./go-cat -E file.txt

Combine flags

./go-cat -n -E file.txt
./go-cat -b -s file.txt

Implementation Notes

• Uses bufio.Scanner for line-based streaming
• Flag priority: -b takes precedence over -n when both are set
• Handles files without trailing newlines correctly
• Clean separation of concerns with LineConfig struct and printLine() helper function

Development Journey

Built incrementally from:

1. Single file reading
2. Multiple file support
3. Stream-based reading optimization
4. Flag parsing and implementation
5. Code refactoring for maintainability