os-lib

README

os-lib

github.com/sds-framework/os-lib is a small Go utility library for the SDS framework. It wraps common operating-system concerns—paths, CLI flags, environment files, processes, and ports—so application code does not have to repeat that logic.

Disclaimer

Applications that call env.LoadAnyEnv() automatically enable .env argument loading. Any application argument without the -- prefix and ending with .env is considered an environment file path and loaded into the process environment. If no .env paths are provided, env.LoadAnyEnv() loads the default .env file.

Packages

path — filesystem helpers

• Resolve the executable's directory (CurrentDir) and build absolute paths relative to it (AbsDir)
• File and directory existence checks that distinguish files from directories (FileExist, DirExist)
• Path parsing: basename, strip extension, split directory and name (FileName, NoExtension, DirAndFileName)
• Create nested directories (MakeDir)
• Platform-specific binary paths: .exe on Windows, plain name on Unix (BinPath)

arg — SDS-style CLI flags

• Flags use --name or --name=value (not the standard library flag package)
• Helpers to list flags, test existence, read values, and build flag strings
• Positional arguments ending in .env are treated as environment file paths (EnvPaths)

env — .env loading and writing

• LoadAnyEnv() reads .env paths from the command line (via arg.EnvPaths()), resolves them relative to the executable directory, and loads them with godotenv into process environment variables (for use with app/config.Config in the wider framework)
• WriteEnv() writes key/value data to a .env file (any type implementing env.KeyValue)

process — process identity and port mapping

• CurrentPid() returns the current process ID
• PortToPid() finds which process is listening on a given TCP port (via go-netstat)

net — port availability

• GetFreePort() picks an unused TCP port
• IsPortUsed() checks whether something is listening on a host:port via a TCP dial

Summary

In short, this library is a thin OS/platform utility layer for SDS applications: where the binary lives, how CLI flags and .env files are parsed, and how to work with ports and processes.

Dependencies

• github.com/joho/godotenv — .env file loading and writing
• github.com/phayes/freeport — free port allocation
• github.com/cakturk/go-netstat — TCP socket / process lookup

Requirements

• Go 1.19+