Golang ошибка eof

Constants

Seek whence values.

const (
    SeekStart   = 0 
    SeekCurrent = 1 
    SeekEnd     = 2 
)

Variables

EOF is the error returned by Read when no more input is available.
(Read must return EOF itself, not an error wrapping EOF,
because callers will test for EOF using ==.)
Functions should return EOF only to signal a graceful end of input.
If the EOF occurs unexpectedly in a structured data stream,
the appropriate error is either ErrUnexpectedEOF or some other error
giving more detail.

var EOF = errors.New("EOF")

ErrClosedPipe is the error used for read or write operations on a closed pipe.

var ErrClosedPipe = errors.New("io: read/write on closed pipe")

ErrNoProgress is returned by some clients of a Reader when
many calls to Read have failed to return any data or error,
usually the sign of a broken Reader implementation.

var ErrNoProgress = errors.New("multiple Read calls return no data or error")

ErrShortBuffer means that a read required a longer buffer than was provided.

var ErrShortBuffer = errors.New("short buffer")

ErrShortWrite means that a write accepted fewer bytes than requested
but failed to return an explicit error.

var ErrShortWrite = errors.New("short write")

ErrUnexpectedEOF means that EOF was encountered in the
middle of reading a fixed-size block or data structure.

var ErrUnexpectedEOF = errors.New("unexpected EOF")

func Copy
¶

func Copy(dst Writer, src Reader) (written int64, err error)

Copy copies from src to dst until either EOF is reached
on src or an error occurs. It returns the number of bytes
copied and the first error encountered while copying, if any.

A successful Copy returns err == nil, not err == EOF.
Because Copy is defined to read from src until EOF, it does
not treat an EOF from Read as an error to be reported.

If src implements WriterTo,
the copy is implemented by calling src.WriteTo(dst).
Otherwise, if dst implements ReaderFrom,
the copy is implemented by calling dst.ReadFrom(src).

some io.Reader stream to be read

func CopyBuffer
¶

func CopyBuffer(dst Writer, src Reader, buf []byte) (written int64, err error)

CopyBuffer is identical to Copy except that it stages through the
provided buffer (if one is required) rather than allocating a
temporary one. If buf is nil, one is allocated; otherwise if it has
zero length, CopyBuffer panics.

If either src implements WriterTo or dst implements ReaderFrom,
buf will not be used to perform the copy.

first reader
second reader

func CopyN
¶

func CopyN(dst Writer, src Reader, n int64) (written int64, err error)

CopyN copies n bytes (or until an error) from src to dst.
It returns the number of bytes copied and the earliest
error encountered while copying.
On return, written == n if and only if err == nil.

If dst implements ReaderFrom, the copy is implemented using it.

func Pipe
¶

func Pipe() (*PipeReader, *PipeWriter)

Pipe creates a synchronous in-memory pipe.
It can be used to connect code expecting an io.Reader
with code expecting an io.Writer.

Reads and Writes on the pipe are matched one to one
except when multiple Reads are needed to consume a single Write.
That is, each Write to the PipeWriter blocks until it has satisfied
one or more Reads from the PipeReader that fully consume
the written data.
The data is copied directly from the Write to the corresponding
Read (or Reads); there is no internal buffering.

It is safe to call Read and Write in parallel with each other or with Close.
Parallel calls to Read and parallel calls to Write are also safe:
the individual calls will be gated sequentially.

some io.Reader stream to be read

func ReadAll
¶

func ReadAll(r Reader) ([]byte, error)

ReadAll reads from r until an error or EOF and returns the data it read.
A successful call returns err == nil, not err == EOF. Because ReadAll is
defined to read from src until EOF, it does not treat an EOF from Read
as an error to be reported.

Go is a general-purpose language designed with systems programming in mind.

func ReadAtLeast
¶

func ReadAtLeast(r Reader, buf []byte, min int) (n int, err error)

ReadAtLeast reads from r into buf until it has read at least min bytes.
It returns the number of bytes copied and an error if fewer bytes were read.
The error is EOF only if no bytes were read.
If an EOF happens after reading fewer than min bytes,
ReadAtLeast returns ErrUnexpectedEOF.
If min is greater than the length of buf, ReadAtLeast returns ErrShortBuffer.
On return, n >= min if and only if err == nil.
If r returns an error having read at least min bytes, the error is dropped.

some io.Reader
error: short buffer
error: unexpected EOF

func ReadFull
¶

func ReadFull(r Reader, buf []byte) (n int, err error)

ReadFull reads exactly len(buf) bytes from r into buf.
It returns the number of bytes copied and an error if fewer bytes were read.
The error is EOF only if no bytes were read.
If an EOF happens after reading some but not all the bytes,
ReadFull returns ErrUnexpectedEOF.
On return, n == len(buf) if and only if err == nil.
If r returns an error having read at least len(buf) bytes, the error is dropped.

some
error: unexpected EOF

func WriteString
¶

func WriteString(w Writer, s string) (n int, err error)

WriteString writes the contents of the string s to w, which accepts a slice of bytes.
If w implements StringWriter, [StringWriter.WriteString] is invoked directly.
Otherwise, [Writer.Write] is called exactly once.

type ByteReader
¶

ByteReader is the interface that wraps the ReadByte method.

ReadByte reads and returns the next byte from the input or
any error encountered. If ReadByte returns an error, no input
byte was consumed, and the returned byte value is undefined.

ReadByte provides an efficient interface for byte-at-time
processing. A Reader that does not implement ByteReader
can be wrapped using bufio.NewReader to add this method.

type ByteReader interface {
    ReadByte() (byte, error)
}

type ByteScanner
¶

ByteScanner is the interface that adds the UnreadByte method to the
basic ReadByte method.

UnreadByte causes the next call to ReadByte to return the last byte read.
If the last operation was not a successful call to ReadByte, UnreadByte may
return an error, unread the last byte read (or the byte prior to the
last-unread byte), or (in implementations that support the Seeker interface)
seek to one byte before the current offset.

type ByteScanner interface {
    ByteReader
    UnreadByte() error
}

type ByteWriter
¶

ByteWriter is the interface that wraps the WriteByte method.

type ByteWriter interface {
    WriteByte(c byte) error
}

type Closer
¶

Closer is the interface that wraps the basic Close method.

The behavior of Close after the first call is undefined.
Specific implementations may document their own behavior.

type Closer interface {
    Close() error
}

type LimitedReader
¶

A LimitedReader reads from R but limits the amount of
data returned to just N bytes. Each call to Read
updates N to reflect the new amount remaining.
Read returns EOF when N <= 0 or when the underlying R returns EOF.

type LimitedReader struct {
    R Reader 
    N int64  
}

func (*LimitedReader) Read
¶

func (l *LimitedReader) Read(p []byte) (n int, err error)

type OffsetWriter
¶

An OffsetWriter maps writes at offset base to offset base+off in the underlying writer.

type OffsetWriter struct {
    
}

func NewOffsetWriter
¶

func NewOffsetWriter(w WriterAt, off int64) *OffsetWriter

NewOffsetWriter returns an OffsetWriter that writes to w
starting at offset off.

func (*OffsetWriter) Seek
¶

func (o *OffsetWriter) Seek(offset int64, whence int) (int64, error)

func (*OffsetWriter) Write
¶

func (o *OffsetWriter) Write(p []byte) (n int, err error)

func (*OffsetWriter) WriteAt
¶

func (o *OffsetWriter) WriteAt(p []byte, off int64) (n int, err error)

type PipeReader
¶

A PipeReader is the read half of a pipe.

type PipeReader struct {
    
}

func (*PipeReader) Close
¶

func (r *PipeReader) Close() error

Close closes the reader; subsequent writes to the
write half of the pipe will return the error ErrClosedPipe.

func (*PipeReader) CloseWithError
¶

func (r *PipeReader) CloseWithError(err error) error

CloseWithError closes the reader; subsequent writes
to the write half of the pipe will return the error err.

CloseWithError never overwrites the previous error if it exists
and always returns nil.

func (*PipeReader) Read
¶

func (r *PipeReader) Read(data []byte) (n int, err error)

Read implements the standard Read interface:
it reads data from the pipe, blocking until a writer
arrives or the write end is closed.
If the write end is closed with an error, that error is
returned as err; otherwise err is EOF.

type PipeWriter
¶

A PipeWriter is the write half of a pipe.

type PipeWriter struct {
    
}

func (*PipeWriter) Close
¶

func (w *PipeWriter) Close() error

Close closes the writer; subsequent reads from the
read half of the pipe will return no bytes and EOF.

func (*PipeWriter) CloseWithError
¶

func (w *PipeWriter) CloseWithError(err error) error

CloseWithError closes the writer; subsequent reads from the
read half of the pipe will return no bytes and the error err,
or EOF if err is nil.

CloseWithError never overwrites the previous error if it exists
and always returns nil.

func (*PipeWriter) Write
¶

func (w *PipeWriter) Write(data []byte) (n int, err error)

Write implements the standard Write interface:
it writes data to the pipe, blocking until one or more readers
have consumed all the data or the read end is closed.
If the read end is closed with an error, that err is
returned as err; otherwise err is ErrClosedPipe.

type ReadCloser
¶

ReadCloser is the interface that groups the basic Read and Close methods.

type ReadCloser interface {
    Reader
    Closer
}

func NopCloser
¶

func NopCloser(r Reader) ReadCloser

NopCloser returns a ReadCloser with a no-op Close method wrapping
the provided Reader r.
If r implements WriterTo, the returned ReadCloser will implement WriterTo
by forwarding calls to r.

type ReadSeekCloser
¶

ReadSeekCloser is the interface that groups the basic Read, Seek and Close
methods.

type ReadSeekCloser interface {
    Reader
    Seeker
    Closer
}

type ReadSeeker
¶

ReadSeeker is the interface that groups the basic Read and Seek methods.

type ReadSeeker interface {
    Reader
    Seeker
}

type ReadWriteCloser
¶

ReadWriteCloser is the interface that groups the basic Read, Write and Close methods.

type ReadWriteCloser interface {
    Reader
    Writer
    Closer
}

type ReadWriteSeeker
¶

ReadWriteSeeker is the interface that groups the basic Read, Write and Seek methods.

type ReadWriteSeeker interface {
    Reader
    Writer
    Seeker
}

type ReadWriter
¶

ReadWriter is the interface that groups the basic Read and Write methods.

type ReadWriter interface {
    Reader
    Writer
}

type Reader
¶

Reader is the interface that wraps the basic Read method.

Read reads up to len(p) bytes into p. It returns the number of bytes
read (0 <= n <= len(p)) and any error encountered. Even if Read
returns n < len(p), it may use all of p as scratch space during the call.
If some data is available but not len(p) bytes, Read conventionally
returns what is available instead of waiting for more.

When Read encounters an error or end-of-file condition after
successfully reading n > 0 bytes, it returns the number of
bytes read. It may return the (non-nil) error from the same call
or return the error (and n == 0) from a subsequent call.
An instance of this general case is that a Reader returning
a non-zero number of bytes at the end of the input stream may
return either err == EOF or err == nil. The next Read should
return 0, EOF.

Callers should always process the n > 0 bytes returned before
considering the error err. Doing so correctly handles I/O errors
that happen after reading some bytes and also both of the
allowed EOF behaviors.

If len(p) == 0, Read should always return n == 0. It may return a
non-nil error if some error condition is known, such as EOF.

Implementations of Read are discouraged from returning a
zero byte count with a nil error, except when len(p) == 0.
Callers should treat a return of 0 and nil as indicating that
nothing happened; in particular it does not indicate EOF.

Implementations must not retain p.

type Reader interface {
    Read(p []byte) (n int, err error)
}

func LimitReader
¶

func LimitReader(r Reader, n int64) Reader

LimitReader returns a Reader that reads from r
but stops with EOF after n bytes.
The underlying implementation is a *LimitedReader.

func MultiReader
¶

func MultiReader(readers ...Reader) Reader

MultiReader returns a Reader that’s the logical concatenation of
the provided input readers. They’re read sequentially. Once all
inputs have returned EOF, Read will return EOF. If any of the readers
return a non-nil, non-EOF error, Read will return that error.

first reader second reader third reader

func TeeReader
¶

func TeeReader(r Reader, w Writer) Reader

TeeReader returns a Reader that writes to w what it reads from r.
All reads from r performed through it are matched with
corresponding writes to w. There is no internal buffering —
the write must complete before the read completes.
Any error encountered while writing is reported as a read error.

some io.Reader stream to be read

type ReaderAt
¶

ReaderAt is the interface that wraps the basic ReadAt method.

ReadAt reads len(p) bytes into p starting at offset off in the
underlying input source. It returns the number of bytes
read (0 <= n <= len(p)) and any error encountered.

When ReadAt returns n < len(p), it returns a non-nil error
explaining why more bytes were not returned. In this respect,
ReadAt is stricter than Read.

Even if ReadAt returns n < len(p), it may use all of p as scratch
space during the call. If some data is available but not len(p) bytes,
ReadAt blocks until either all the data is available or an error occurs.
In this respect ReadAt is different from Read.

If the n = len(p) bytes returned by ReadAt are at the end of the
input source, ReadAt may return either err == EOF or err == nil.

If ReadAt is reading from an input source with a seek offset,
ReadAt should not affect nor be affected by the underlying
seek offset.

Clients of ReadAt can execute parallel ReadAt calls on the
same input source.

Implementations must not retain p.

type ReaderAt interface {
    ReadAt(p []byte, off int64) (n int, err error)
}

type ReaderFrom
¶

ReaderFrom is the interface that wraps the ReadFrom method.

ReadFrom reads data from r until EOF or error.
The return value n is the number of bytes read.
Any error except EOF encountered during the read is also returned.

The Copy function uses ReaderFrom if available.

type ReaderFrom interface {
    ReadFrom(r Reader) (n int64, err error)
}

type RuneReader
¶

RuneReader is the interface that wraps the ReadRune method.

ReadRune reads a single encoded Unicode character
and returns the rune and its size in bytes. If no character is
available, err will be set.

type RuneReader interface {
    ReadRune() (r rune, size int, err error)
}

type RuneScanner
¶

RuneScanner is the interface that adds the UnreadRune method to the
basic ReadRune method.

UnreadRune causes the next call to ReadRune to return the last rune read.
If the last operation was not a successful call to ReadRune, UnreadRune may
return an error, unread the last rune read (or the rune prior to the
last-unread rune), or (in implementations that support the Seeker interface)
seek to the start of the rune before the current offset.

type RuneScanner interface {
    RuneReader
    UnreadRune() error
}

type SectionReader
¶

SectionReader implements Read, Seek, and ReadAt on a section
of an underlying ReaderAt.

type SectionReader struct {
    
}

func NewSectionReader
¶

func NewSectionReader(r ReaderAt, off int64, n int64) *SectionReader

NewSectionReader returns a SectionReader that reads from r
starting at offset off and stops with EOF after n bytes.

func (*SectionReader) Read
¶

func (s *SectionReader) Read(p []byte) (n int, err error)

func (*SectionReader) ReadAt
¶

func (s *SectionReader) ReadAt(p []byte, off int64) (n int, err error)

func (*SectionReader) Seek
¶

func (s *SectionReader) Seek(offset int64, whence int) (int64, error)

func (*SectionReader) Size
¶

func (s *SectionReader) Size() int64

Size returns the size of the section in bytes.

type Seeker
¶

Seeker is the interface that wraps the basic Seek method.

Seek sets the offset for the next Read or Write to offset,
interpreted according to whence:
SeekStart means relative to the start of the file,
SeekCurrent means relative to the current offset, and
SeekEnd means relative to the end
(for example, offset = -2 specifies the penultimate byte of the file).
Seek returns the new offset relative to the start of the
file or an error, if any.

Seeking to an offset before the start of the file is an error.
Seeking to any positive offset may be allowed, but if the new offset exceeds
the size of the underlying object the behavior of subsequent I/O operations
is implementation-dependent.

type Seeker interface {
    Seek(offset int64, whence int) (int64, error)
}

type StringWriter
¶

StringWriter is the interface that wraps the WriteString method.

type StringWriter interface {
    WriteString(s string) (n int, err error)
}

type WriteCloser
¶

WriteCloser is the interface that groups the basic Write and Close methods.

type WriteCloser interface {
    Writer
    Closer
}

type WriteSeeker
¶

WriteSeeker is the interface that groups the basic Write and Seek methods.

type WriteSeeker interface {
    Writer
    Seeker
}

type Writer
¶

Writer is the interface that wraps the basic Write method.

Write writes len(p) bytes from p to the underlying data stream.
It returns the number of bytes written from p (0 <= n <= len(p))
and any error encountered that caused the write to stop early.
Write must return a non-nil error if it returns n < len(p).
Write must not modify the slice data, even temporarily.

Implementations must not retain p.

type Writer interface {
    Write(p []byte) (n int, err error)
}

Discard is a Writer on which all Write calls succeed
without doing anything.

var Discard Writer = discard{}

func MultiWriter
¶

func MultiWriter(writers ...Writer) Writer

MultiWriter creates a writer that duplicates its writes to all the
provided writers, similar to the Unix tee(1) command.

Each write is written to each listed writer, one at a time.
If a listed writer returns an error, that overall write operation
stops and returns the error; it does not continue down the list.

some io.Reader stream to be read
some io.Reader stream to be read

type WriterAt
¶

WriterAt is the interface that wraps the basic WriteAt method.

WriteAt writes len(p) bytes from p to the underlying data stream
at offset off. It returns the number of bytes written from p (0 <= n <= len(p))
and any error encountered that caused the write to stop early.
WriteAt must return a non-nil error if it returns n < len(p).

If WriteAt is writing to a destination with a seek offset,
WriteAt should not affect nor be affected by the underlying
seek offset.

Clients of WriteAt can execute parallel WriteAt calls on the same
destination if the ranges do not overlap.

Implementations must not retain p.

type WriterAt interface {
    WriteAt(p []byte, off int64) (n int, err error)
}

type WriterTo
¶

WriterTo is the interface that wraps the WriteTo method.

WriteTo writes data to w until there’s no more data to write or
when an error occurs. The return value n is the number of bytes
written. Any error encountered during the write is also returned.

The Copy function uses WriterTo if available.

type WriterTo interface {
    WriteTo(w Writer) (n int64, err error)
}