std / io

io

import "std:io"

Provides fundamental I/O abstractions for reading and writing data. Defines generic Reader, Writer, Closer, and composite types (ReadWriter, ReadCloser, WriteCloser, ReadWriteCloser) for callback-based I/O.

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Index

Types Error Constants NewReader NewWriter NewCloser NewReadWriter NewReadCloser NewWriteCloser NewReadWriteCloser Read Write ReadAll WriteAll CloseCloser ReadRW WriteRW ReadRC CloseRC WriteWC CloseWC ReadRWC WriteRWC CloseRWC ReaderFromRW WriterFromRW ReaderFromRC WriterFromWC ReaderFromRWC WriterFromRWC Copy NopCloser

Types

# 
type Error int

Represents an I/O error code.

# 
type Reader struct { /* unexported fields */ }

Provides generic reading via callback.

# 
type Writer struct { /* unexported fields */ }

Provides generic writing via callback.

# 
type Closer struct { /* unexported fields */ }

Provides generic closing via callback.

# 
type ReadWriter struct { /* unexported fields */ }

Combines reading and writing via callbacks.

# 
type ReadCloser struct { /* unexported fields */ }

Combines reading and closing via callbacks.

# 
type WriteCloser struct { /* unexported fields */ }

Combines writing and closing via callbacks.

# 
type ReadWriteCloser struct { /* unexported fields */ }

Combines reading, writing, and closing via callbacks.

Error Constants

# 
const (
    OK          Error = iota
    EOF
    ErrClosed
    ErrInvalid
    ErrIO
    ErrNoMem
    ErrPerm
    ErrExist
    ErrNotExist
)

Error constants: OK indicates success, EOF indicates end of stream, ErrClosed indicates the stream is closed, ErrInvalid indicates an invalid argument, ErrIO indicates an underlying I/O error, ErrNoMem indicates out of memory, ErrPerm indicates a permission error, ErrExist indicates the file already exists, and ErrNotExist indicates the file does not exist.

Generic Reader/Writer

# 
func NewReader(source any, readFn func(any, []byte) (int, Error)) Reader

Creates a Reader with the given source and read callback.

# 
func NewWriter(dest any, writeFn func(any, []byte) (int, Error)) Writer

Creates a Writer with the given destination and write callback.

# 
func Read(r Reader, buf []byte) (int, Error)

Reads up to len(buf) bytes from the Reader into buf.

# 
func Write(w Writer, buf []byte) (int, Error)

Writes buf to the Writer.

# 
func ReadAll(r Reader) (list[byte], Error)

Reads from the Reader until EOF. Caller must free the result.

# 
func WriteAll(w Writer, buf []byte) Error

Writes all bytes from buf to the Writer.

Composite Constructors

# 
func NewCloser(target any, closeFn func(any) Error) Closer

Creates a Closer with the given target and close callback.

# 
func NewReadWriter(target any, readFn func(any, []byte) (int, Error), writeFn func(any, []byte) (int, Error)) ReadWriter

Creates a ReadWriter with the given target, read callback, and write callback.

# 
func NewReadCloser(target any, readFn func(any, []byte) (int, Error), closeFn func(any) Error) ReadCloser

Creates a ReadCloser with the given target, read callback, and close callback.

# 
func NewWriteCloser(target any, writeFn func(any, []byte) (int, Error), closeFn func(any) Error) WriteCloser

Creates a WriteCloser with the given target, write callback, and close callback.

# 
func NewReadWriteCloser(target any, readFn func(any, []byte) (int, Error), writeFn func(any, []byte) (int, Error), closeFn func(any) Error) ReadWriteCloser

Creates a ReadWriteCloser with the given target, read callback, write callback, and close callback.

Composite Operations

# 
func CloseCloser(c Closer) Error

Closes the Closer by invoking its close callback.

# 
func ReadRW(rw ReadWriter, buf []byte) (int, Error)

Reads from a ReadWriter into buf.

# 
func WriteRW(rw ReadWriter, buf []byte) (int, Error)

Writes buf to a ReadWriter.

# 
func ReadRC(rc ReadCloser, buf []byte) (int, Error)

Reads from a ReadCloser into buf.

# 
func CloseRC(rc ReadCloser) Error

Closes a ReadCloser.

# 
func WriteWC(wc WriteCloser, buf []byte) (int, Error)

Writes buf to a WriteCloser.

# 
func CloseWC(wc WriteCloser) Error

Closes a WriteCloser.

# 
func ReadRWC(rwc ReadWriteCloser, buf []byte) (int, Error)

Reads from a ReadWriteCloser into buf.

# 
func WriteRWC(rwc ReadWriteCloser, buf []byte) (int, Error)

Writes buf to a ReadWriteCloser.

# 
func CloseRWC(rwc ReadWriteCloser) Error

Closes a ReadWriteCloser.

Extractors

# 
func ReaderFromRW(rw ReadWriter) Reader

Extracts a Reader from a ReadWriter.

# 
func WriterFromRW(rw ReadWriter) Writer

Extracts a Writer from a ReadWriter.

# 
func ReaderFromRC(rc ReadCloser) Reader

Extracts a Reader from a ReadCloser.

# 
func WriterFromWC(wc WriteCloser) Writer

Extracts a Writer from a WriteCloser.

# 
func ReaderFromRWC(rwc ReadWriteCloser) Reader

Extracts a Reader from a ReadWriteCloser.

# 
func WriterFromRWC(rwc ReadWriteCloser) Writer

Extracts a Writer from a ReadWriteCloser.

Utilities

# 
func Copy(dst Writer, src Reader) (int, Error)

Copies from Reader to Writer until EOF.

# 
func NopCloser(r Reader) ReadCloser

Wraps a Reader with a no-op Close.