Namespace: go.std.compress.gzip

v1.0

Contents

• Summary
• Index
• Constants
• Variables
• Functions, Macros, and Special Forms
• Types

Summary

Provides a low-level interface to the compress/gzip package.

Package gzip implements reading and writing of gzip format compressed files,
as specified in RFC 1952.

Index

• *Header
• *Reader
• *Writer
• BestCompression
• BestSpeed
• DefaultCompression
• ErrChecksum
• ErrHeader
• Header
• HuffmanOnly
• NewReader
• NewWriter
• NewWriterLevel
• NoCompression
• Reader
• Writer
• arrayOfHeader
• arrayOfReader
• arrayOfWriter

Legend

Constant Variable Function Macro Special form Type GoVar Receiver/Method

Constants

Constants are variables with :const true in their metadata. Joker currently does not recognize them as special; as such, it allows redefining them or their values.

• BestCompression

  Int v1.0

  These constants are copied from the flate package, so that code that imports
  "compress/gzip" does not also have to import "compress/flate".
  

• BestSpeed

  Int v1.0

  These constants are copied from the flate package, so that code that imports
  "compress/gzip" does not also have to import "compress/flate".
  

• DefaultCompression

  Int v1.0

  These constants are copied from the flate package, so that code that imports
  "compress/gzip" does not also have to import "compress/flate".
  

• HuffmanOnly

  Int v1.0

  These constants are copied from the flate package, so that code that imports
  "compress/gzip" does not also have to import "compress/flate".
  

• NoCompression

  Int v1.0

  These constants are copied from the flate package, so that code that imports
  "compress/gzip" does not also have to import "compress/flate".
  

Variables

• ErrChecksum

  Var v1.0

  ErrChecksum is returned when reading GZIP data that has an invalid checksum.
  

• ErrHeader

  Var v1.0

  ErrHeader is returned when reading GZIP data that has an invalid header.
  

Functions, Macros, and Special Forms

• NewReader

  Function v1.0

  (NewReader r)
  

  NewReader creates a new Reader reading the given reader.
  If r does not also implement io.ByteReader,
  the decompressor may read more data than necessary from r.
  
  It is the caller's responsibility to call Close on the Reader when done.
  
  The Reader.Header fields will be valid in the Reader returned.
  
  Go input arguments: (r io.Reader)
  
  Go returns: (*Reader, error)
  
  Joker input arguments: [^go.std.io/Reader r]
  
  Joker returns: [^*Reader, ^Error]

• NewWriter

  Function v1.0

  (NewWriter w)
  

  NewWriter returns a new Writer.
  Writes to the returned writer are compressed and written to w.
  
  It is the caller's responsibility to call Close on the Writer when done.
  Writes may be buffered and not flushed until Close.
  
  Callers that wish to set the fields in Writer.Header must do so before
  the first call to Write, Flush, or Close.
  
  Go input arguments: (w io.Writer)
  
  Go returns: *Writer
  
  Joker input arguments: [^go.std.io/Writer w]
  
  Joker returns: ^*Writer

• NewWriterLevel

  Function v1.0

  (NewWriterLevel w level)
  

  NewWriterLevel is like NewWriter but specifies the compression level instead
  of assuming DefaultCompression.
  
  The compression level can be DefaultCompression, NoCompression, HuffmanOnly
  or any integer value between BestSpeed and BestCompression inclusive.
  The error returned will be nil if the level is valid.
  
  Go input arguments: (w io.Writer, level int)
  
  Go returns: (*Writer, error)
  
  Joker input arguments: [^go.std.io/Writer w, ^Int level]
  
  Joker returns: [^*Writer, ^Error]

Types

• *Header

  Concrete Type v1.0

  The gzip file stores a header giving metadata about the compressed file.
  That header is exposed as the fields of the Writer and Reader structs.
  
  Strings must be UTF-8 encoded and may only contain Unicode code points
  U+0001 through U+00FF, due to limitations of the GZIP file format.
  

• *Reader

  Concrete Type v1.0

  A Reader is an io.Reader that can be read to retrieve
  uncompressed data from a gzip-format compressed file.
  
  In general, a gzip file can be a concatenation of gzip files,
  each with its own header. Reads from the Reader
  return the concatenation of the uncompressed data of each.
  Only the first header is recorded in the Reader fields.
  
  Gzip files store a length and checksum of the uncompressed data.
  The Reader will return an ErrChecksum when Read
  reaches the end of the uncompressed data if it does not
  have the expected length or checksum. Clients should treat data
  returned by Read as tentative until they receive the io.EOF
  marking the end of the data.
  

• Close

  Receiver for *Reader v1.0

  ([])
  

  Close closes the Reader. It does not close the underlying io.Reader.
  In order for the GZIP checksum to be verified, the reader must be
  fully consumed until the io.EOF.
  

• Multistream

  Receiver for *Reader v1.0

  ([ok])
  

  Multistream controls whether the reader supports multistream files.
  
  If enabled (the default), the Reader expects the input to be a sequence
  of individually gzipped data streams, each with its own header and
  trailer, ending at EOF. The effect is that the concatenation of a sequence
  of gzipped files is treated as equivalent to the gzip of the concatenation
  of the sequence. This is standard behavior for gzip readers.
  
  Calling Multistream(false) disables this behavior; disabling the behavior
  can be useful when reading file formats that distinguish individual gzip
  data streams or mix gzip data streams with other data streams.
  In this mode, when the Reader reaches the end of the data stream,
  Read returns io.EOF. The underlying reader must implement io.ByteReader
  in order to be left positioned just after the gzip stream.
  To start the next stream, call z.Reset(r) followed by z.Multistream(false).
  If there is no next stream, z.Reset(r) will return io.EOF.
  

• Read

  Receiver for *Reader v1.0

  ([p])
  

  Read implements io.Reader, reading uncompressed bytes from its underlying Reader.
  

• Reset

  Receiver for *Reader v1.0

  ([r])
  

  Reset discards the Reader z's state and makes it equivalent to the
  result of its original state from NewReader, but reading from r instead.
  This permits reusing a Reader rather than allocating a new one.
  

• *Writer

  Concrete Type v1.0

  A Writer is an io.WriteCloser.
  Writes to a Writer are compressed and written to w.
  

• Close

  Receiver for *Writer v1.0

  ([])
  

  Close closes the Writer by flushing any unwritten data to the underlying
  io.Writer and writing the GZIP footer.
  It does not close the underlying io.Writer.
  

• Flush

  Receiver for *Writer v1.0

  ([])
  

  Flush flushes any pending compressed data to the underlying writer.
  
  It is useful mainly in compressed network protocols, to ensure that
  a remote reader has enough data to reconstruct a packet. Flush does
  not return until the data has been written. If the underlying
  writer returns an error, Flush returns that error.
  
  In the terminology of the zlib library, Flush is equivalent to Z_SYNC_FLUSH.
  

• Reset

  Receiver for *Writer v1.0

  ([w])
  

  Reset discards the Writer z's state and makes it equivalent to the
  result of its original state from NewWriter or NewWriterLevel, but
  writing to w instead. This permits reusing a Writer rather than
  allocating a new one.
  

• Write

  Receiver for *Writer v1.0

  ([p])
  

  Write writes a compressed form of p to the underlying io.Writer. The
  compressed bytes are not necessarily flushed until the Writer is closed.
  

• Header

  Concrete Type v1.0

  The gzip file stores a header giving metadata about the compressed file.
  That header is exposed as the fields of the Writer and Reader structs.
  
  Strings must be UTF-8 encoded and may only contain Unicode code points
  U+0001 through U+00FF, due to limitations of the GZIP file format.
  

• Reader

  Concrete Type v1.0

  A Reader is an io.Reader that can be read to retrieve
  uncompressed data from a gzip-format compressed file.
  
  In general, a gzip file can be a concatenation of gzip files,
  each with its own header. Reads from the Reader
  return the concatenation of the uncompressed data of each.
  Only the first header is recorded in the Reader fields.
  
  Gzip files store a length and checksum of the uncompressed data.
  The Reader will return an ErrChecksum when Read
  reaches the end of the uncompressed data if it does not
  have the expected length or checksum. Clients should treat data
  returned by Read as tentative until they receive the io.EOF
  marking the end of the data.
  

• Writer

  Concrete Type v1.0

  A Writer is an io.WriteCloser.
  Writes to a Writer are compressed and written to w.
  

• arrayOfHeader

  Concrete Type v1.0

  The gzip file stores a header giving metadata about the compressed file.
  That header is exposed as the fields of the Writer and Reader structs.
  
  Strings must be UTF-8 encoded and may only contain Unicode code points
  U+0001 through U+00FF, due to limitations of the GZIP file format.
  

• arrayOfReader

  Concrete Type v1.0

  A Reader is an io.Reader that can be read to retrieve
  uncompressed data from a gzip-format compressed file.
  
  In general, a gzip file can be a concatenation of gzip files,
  each with its own header. Reads from the Reader
  return the concatenation of the uncompressed data of each.
  Only the first header is recorded in the Reader fields.
  
  Gzip files store a length and checksum of the uncompressed data.
  The Reader will return an ErrChecksum when Read
  reaches the end of the uncompressed data if it does not
  have the expected length or checksum. Clients should treat data
  returned by Read as tentative until they receive the io.EOF
  marking the end of the data.
  

• arrayOfWriter

  Concrete Type v1.0

  A Writer is an io.WriteCloser.
  Writes to a Writer are compressed and written to w.