Os package
The os package is a Go standard-library package providing portable interfaces for operating-system functionality, including files, processes, environment variables, and arguments.
Go in Action, Second Edition
The os package is a Go standard-library package that provides platform-independent interfaces for operating-system functionality, including files, processes, and environment variables.
- How it is used
- Connects Go CLI programs to files, arguments, standard streams, environment variables, and process exit status.
- How deep it goes
- Works through file reading and CLI stream selection, then addresses metadata checks and exit behavior without examining operating-system internals.
- Examples
- Uses a file-based word counter and a JSON/XML conversion CLI with selectable input and output files.
- What you can do after
- Apply it via Go’s os package to read inputs, select streams, inspect settings, and report CLI failures.
Go in Practice, Second Edition
The Go os package provides portable functions for interacting with operating-system facilities such as environment variables, files, and processes.
- How it is used
- Deploys operating-system access for environment configuration, host detection, process inspection, and portable path handling.
- How deep it goes
- Explains concrete functions and runnable patterns, including validation and package composition, but stops short of broader os facilities.
- Examples
- Uses PORT-based HTTP startup, hostname-to-address lookup, and executable availability checks.
- What you can do after
- Apply it via os functions to configure services, inspect hosts, and construct portable runtime checks.
Read how Go in Practice, Second Edition explains os package →
Learn Go with Pocket-Sized Projects
The os package is a Go standard-library package that provides operating-system-related functionality, including access to process arguments.
- How it is used
- Provides operating-system access for opening, creating, modifying, and managing files.
- How deep it goes
- Explains os.File, os.Open, returned errors, and distinctions among common file-opening functions.
- Examples
- Uses a loadBookworms function that opens a path, checks the error, and defers closing the file.
- What you can do after
- Operate files with os.Open, choose alternative opening functions, and propagate file-opening errors.
Read how Learn Go with Pocket-Sized Projects explains os package →
Related concepts
- os.ReadFilehas part · os.ReadFile is a Go standard-library function that reads an entire named file and returns its contents as a byte slice and an error.
- environment variableuses · An environment variable is a named value supplied through an operating-system or process environment and made available to programs for runtime configuration or information.
- file systemuses · A file system is a software-managed structure and interface for organizing, naming, storing, and accessing files and directories on storage.
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