Symlink Utility

A Bash utility that creates symbolic links in /usr/local/bin for executables, making them accessible system-wide. Designed for managing scripts across multiple directories with built-in safety and batch processing.

Primary Use Case: .symlink Files

Create a .symlink file in any project directory listing executables to make available system-wide:

# Comments start with #
  # Indented comments are valid

script1                       # → script1 (inline comments stripped)
tools/script2                 # → script2
build.bash build              # → build (custom name)
util.sh helper util-cmd       # → helper AND util-cmd (multiple links)
my\ script.sh                 # → "my script.sh" (escaped space in source)
my\ script.sh myscript        # → myscript (escaped source, custom name)

Format: <source> [<linkname>...] — paths relative to .symlink location.

Parsing rules:

1. Strip inline comments (# to end of line)
2. Trim leading/trailing whitespace
3. Skip empty lines
4. First token = source file (supports \ for literal spaces), remaining tokens = link names
5. If no link names specified, use basename(source)
6. Link names do NOT support spaces (commands in /usr/local/bin shouldn't have spaces)

Process all .symlink files in a directory tree:

sudo symlink -SPd /my/scripts

This scans for .symlink files (max depth 5), creates symlinks, skips prompts for existing links (-P), and cleans broken symlinks (-d).

Installation

# Clone and install
git clone https://github.com/user/symlink.git
cd symlink
./symlink -S

# Verify
symlink --version

Usage Examples

# Main usage - scan with no prompts, clean broken links
sudo symlink -SPd /my/scripts

# Scan current directory
sudo symlink -SPd

# List .symlink contents without creating links
symlink -l /path/to/projects

# Single file symlinking
sudo symlink /path/to/script

# Dry-run to preview changes
symlink -n ./my-script.sh

# Debug mode
symlink --debug -nSPd /path/to/scripts

Command-Line Options

Option	Description
-S, --scan-symlink	Scan for .symlink files and process them
-P, --no-prompt	Skip confirmation prompts for existing symlinks
-d, --delete-broken-symlinks	Clean up broken symlinks in target directory
-t, --target-dir DIR	Custom target directory (default: /usr/local/bin)
-l, --list	List .symlink file contents only
-n, --dry-run	Preview changes without executing
-v, --verbose	Verbose output
-q, --quiet	Suppress informational messages
-D, --debug	Debug mode with trace logging
-h, --help	Display help
-V, --version	Show version

Options can be combined: -SPd for no-prompt scan with cleanup.

Safety Features

Protects 53 critical system binaries from accidental replacement, limits scan depth to 5 levels, applies timeouts during path resolution, and auto-detects interactive mode for appropriate prompting.

Environment Variables

Variable	Purpose
SYMLINK_DEBUG=1	Enable debug logging to /tmp/symlink-trace-<user>-<pid>.log
SYMLINK_FORCE_CRITICAL=1	Bypass critical file protection (use with caution)

Exit Codes

Code	Meaning
0	Success
1	General error
2	Permission denied
3	File not found
22	Invalid option
50	No symlink files found

Requirements

• Bash 5.2+
• Root privileges (auto-elevates with sudo)
• Standard Linux utilities (realpath, timeout)

License

GPL-3.0 - GNU General Public License v3.0

Contributing

Contributions welcome via Pull Requests.