Os.Open
os.Open is a Go standard-library function that opens a named file for reading and returns a file handle and error.
Learn Go with Pocket-Sized Projects
os.Open is a Go os-package function that opens a named file for reading and returns an os.File pointer or an error.
- How it is used
- Opens a path for reading while supporting error propagation and later file operations.
- How deep it goes
- Defines the return values and read-only behavior, then demonstrates error checking and deferred closing.
- Examples
- Uses a file path, an os.Open call, an error branch, and defer f.Close in a bookworm data loader.
- What you can do after
- Apply it via Go's os package to open readable files, handle failures, and arrange descriptor cleanup.
Read how Learn Go with Pocket-Sized Projects explains os.Open →
Go in Practice, Second Edition
os.Open is a Go standard-library function that opens a file and returns a file handle for subsequent operations.
- How it is used
- Supports file inspection and sequential processing when reading the entire file would be inefficient.
- How deep it goes
- Explains opening, error handling, closure, metadata inspection, and incremental reads, but stops short of broader file-management operations.
- Examples
- Uses structured.log, file.Stat(), newline-separated JSON records, and bufio.Scanner.
- What you can do after
- Operate/configure file handles to inspect metadata and process large, structured files incrementally.
Related concepts
- os.Fileproduces · os.File is a Go standard-library type representing an open file or other operating-system file handle and providing associated file operations.
- os.OpenFilealternative to · os.OpenFile is a Go standard-library function that opens or creates a named file according to specified flags and permissions.
- os.ReadFilealternative to · 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.
- go:embed directivealternative to · The go:embed directive is a Go compiler feature that incorporates specified file or directory contents into program variables and the compiled binary.
- bufio.Scanneruses · bufio.Scanner is a Go type that reads input and advances through it as successive tokens.
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