if len(record) != size {
		size = len(record)
		record = strconv.Itoa(size) + " " + k + "=" + v + "\n"
	}
	return record, nil
}

// validPAXRecord reports whether the key-value pair is valid where each
// record is formatted as:
//
//	"%d %s=%s\n" % (size, key, value)
//
// Keys and values should be UTF-8, but the number of bad writers out there
// forces us to be a more liberal.

pkg net, method (*UDPConn) WriteToUDPAddrPort([]uint8, netip.AddrPort) (int, error)
pkg net, type Error interface, Temporary //deprecated
pkg net/http, func MaxBytesHandler(Handler, int64) Handler
pkg net/http, method (*Cookie) Valid() error
pkg net/netip, func AddrFrom16([16]uint8) Addr
pkg net/netip, func AddrFrom4([4]uint8) Addr
pkg net/netip, func AddrFromSlice([]uint8) (Addr, bool)
pkg net/netip, func AddrPortFrom(Addr, uint16) AddrPort

func (b *block) toUSTAR() *headerUSTAR { return (*headerUSTAR)(b) }
func (b *block) toSparse() sparseArray { return sparseArray(b[:]) }

// getFormat checks that the block is a valid tar header based on the checksum.
// It then attempts to guess the specific format based on magic values.
// If the checksum fails, then FormatUnknown is returned.
func (b *block) getFormat() Format {
	// Verify checksum.

	//
	// This flag should only be set if the user intends to encode a non-portable
	// ZIP file for a specific localized region. Otherwise, the Writer
	// automatically sets the ZIP format's UTF-8 flag for valid UTF-8 strings.
	NonUTF8 bool

	CreatorVersion uint16
	ReaderVersion  uint16
	Flags          uint16

	// Method is the compression method. If zero, Store is used.
	Method uint16

		if !p.allowABI {
			if issueError {
				p.errorf("ABI selector only permitted when compiling runtime, reference was to %q", name)
			}
		} else {
			theabi, valid := obj.ParseABI(abistr)
			if !valid {
				if issueError {
					p.errorf("malformed ABI selector %q in reference to %q",
						abistr, name)
				}
			} else {
				abi = theabi
			}
		}
	}
	p.get('>')

	// Fast path 1: ASCII.
	if data[0] < utf8.RuneSelf {
		return 1, data[0:1], nil
	}

	// Fast path 2: Correct UTF-8 decode without error.
	_, width := utf8.DecodeRune(data)
	if width > 1 {
		// It's a valid encoding. Width cannot be one for a correctly encoded
		// non-ASCII rune.
		return width, data[0:width], nil
	}

	// We know it's an error: we have width==1 and implicitly r==utf8.RuneError.

	vectors := []struct {
		input string // Input stream
		cnt   int    // Expected number of headers read
		err   error  // Expected error outcome
	}{
		{"", 0, io.EOF}, // Empty file is a "valid" tar file
		{data1[:511], 0, io.ErrUnexpectedEOF},
		{data1[:512], 1, io.ErrUnexpectedEOF},
		{data1[:1024], 1, io.EOF},
		{data1[:1536], 2, io.ErrUnexpectedEOF},
		{data1[:2048], 2, io.EOF},
		{data1, 2, io.EOF},

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// This contains the majority of valid opcode combinations
// available in cmd/internal/obj/ppc64/asm9.go with
// their valid instruction encodings.

#include "../../../../../runtime/textflag.h"

// In case of index mode instructions, usage of
// (Rx)(R0) is equivalent to (Rx+R0)

\n   U+000A line feed or newline
\r   U+000D carriage return
\t   U+0009 horizontal tab
\v   U+000B vertical tab
\\   U+005C backslash
\'   U+0027 single quote  (valid escape only within rune literals)
\"   U+0022 double quote  (valid escape only within string literals)
</pre>

<p>
An unrecognized character following a backslash in a rune literal is illegal.
</p>

<pre class="ebnf">

		if i > 0 {
			name, value = name[:i], name[i+1:]
		}
		tokens := Tokenize(name)
		if len(tokens) != 1 || tokens[0].ScanToken != scanner.Ident {
			fmt.Fprintf(os.Stderr, "asm: parsing -D: %q is not a valid identifier name\n", tokens[0])
			flags.Usage()
		}
		macros[name] = &Macro{
			name:   name,
			args:   nil,
			tokens: Tokenize(value),
		}
	}
	return macros
}