environment variables work in a similar way for C++ code.

# Go references to C

Within the Go file, C's struct field names that are keywords in Go
can be accessed by prefixing them with an underscore: if x points at a C
struct with a field named "type", x._type accesses the field.
C struct fields that cannot be expressed in Go, such as bit fields
or misaligned data, are omitted in the Go struct, replaced by

	bodyOffset, err := f.findBodyOffset()
	if err != nil {
		return
	}
	return f.headerOffset + bodyOffset, nil
}

// Open returns a [ReadCloser] that provides access to the [File]'s contents.
// Multiple files may be read concurrently.
func (f *File) Open() (io.ReadCloser, error) {
	bodyOffset, err := f.findBodyOffset()
	if err != nil {
		return nil, err
	}

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Package tar implements access to tar archives.
//
// Tape archives (tar) are a file format for storing a sequence of files that
// can be read and written in a streaming manner.
// This package aims to cover most variations of the format,
// including those produced by GNU and BSD tar tools.

in the Go assembler the names <code>SP</code> and <code>PC</code>
are still treated specially;
for instance, references to <code>SP</code> require a symbol,
much like <code>FP</code>.
To access the actual hardware register use the true <code>R</code> name.
For example, on the ARM architecture the hardware
<code>SP</code> and <code>PC</code> are accessible as
<code>R13</code> and <code>R15</code>.
</p>

<p>

					f.Preamble += "#line 1 \"cgo-generated-wrapper\"\n"
				}
			}

		case *ast.FuncDecl:
			// Also, reject attempts to declare methods on C.T or *C.T.
			// (The generated code would otherwise accept this
			// invalid input; see issue #57926.)
			if decl.Recv != nil && len(decl.Recv.List) > 0 {
				recvType := decl.Recv.List[0].Type
				if recvType != nil {
					t := recvType

observe values produced by writes to the same variable in a different goroutine.
</p>


<h3 id="advice">Advice</h3>

<p>
Programs that modify data being simultaneously accessed by multiple goroutines
must serialize such access.
</p>

<p>
To serialize access, protect the data with channel operations or other synchronization primitives
such as those in the <a href="/pkg/sync/"><code>sync</code></a>

type repeatedByte struct {
	off int64
	b   byte
	n   int64
}

// rleBuffer is a run-length-encoded byte buffer.
// It's an io.Writer (like a bytes.Buffer) and also an io.ReaderAt,
// allowing random-access reads.
type rleBuffer struct {
	buf []repeatedByte
}

func (r *rleBuffer) Size() int64 {
	if len(r.buf) == 0 {
		return 0
	}
	last := &r.buf[len(r.buf)-1]
	return last.off + last.n
}

package tar

import (
	"bytes"
	"io"
	"path/filepath"
	"strconv"
	"strings"
	"time"
)

// Reader provides sequential access to the contents of a tar archive.
// Reader.Next advances to the next file in the archive (including the first),
// and then Reader can be treated as an io.Reader to access the file's data.
type Reader struct {
	r    io.Reader
	pad  int64      // Amount of padding (ignored) after current file entry

client or server to have an empty Content-Length header.
This behavior is controlled by the `httplaxcontentlength` setting.

Go 1.22 changed the behavior of ServeMux to accept extended
patterns and unescape both patterns and request paths by segment.
This behavior can be controlled by the
[`httpmuxgo121` setting](/pkg/net/http/#ServeMux).

	RegisterNumber func(string, int16) (int16, bool)
	// Instruction is a jump.
	IsJump func(word string) bool
}

// nilRegisterNumber is the register number function for architectures
// that do not accept the R(N) notation. It always returns failure.
func nilRegisterNumber(name string, n int16) (int16, bool) {
	return 0, false
}

// Set configures the architecture specified by GOARCH and returns its representation.