// scanners.
func (s *Scanner) Scan() bool {
	if s.done {
		return false
	}
	s.scanCalled = true
	// Loop until we have a token.
	for {
		// See if we can get a token with what we already have.
		// If we've run out of data but have an error, give the split function
		// a chance to recover any remaining, possibly empty token.
		if s.end > s.start || s.err != nil {
			advance, token, err := s.split(s.buf[s.start:s.end], s.err != nil)

	for len(s) > 0 && s[0] == c {
		s = s[1:]
	}
	if len(s) == 0 {
		// This is what we've historically done.
		return nil
	}
	return s
}

func trimLeftASCII(s []byte, as *asciiSet) []byte {
	for len(s) > 0 {
		if !as.contains(s[0]) {
			break
		}
		s = s[1:]
	}
	if len(s) == 0 {
		// This is what we've historically done.
		return nil
	}
	return s
}

				} else {
					err = err1
				}
			} else if r.hash.Sum32() != r.f.CRC32 {
				err = ErrChecksum
			}
		} else {
			// If there's not a data descriptor, we still compare
			// the CRC32 of what we've read against the file header
			// or TOC's CRC32, if it seems like it was set.
			if r.f.CRC32 != 0 && r.hash.Sum32() != r.f.CRC32 {
				err = ErrChecksum
			}
		}
	}
	r.err = err
	return
}

	foundAThread := false
	for _, f := range fs {
		tf := fmt.Sprintf("/proc/%s/status", f.Name())
		d, err := os.ReadFile(tf)
		if err != nil {
			// There are a surprising number of ways this
			// can error out on linux.  We've seen all of
			// the following, so treat any error here as
			// equivalent to the "process is gone":
			//    os.IsNotExist(err),
			//    "... : no such process",
			//    "... : bad file descriptor.
			continue
		}

next:
	// Skip newlines.
	var tok lex.ScanToken
	for {
		tok = p.nextToken()
		// We save the line number here so error messages from this instruction
		// are labeled with this line. Otherwise we complain after we've absorbed
		// the terminating newline and the line numbers are off by one in errors.
		p.lineNum = p.lex.Line()
		switch tok {
		case '\n', ';':
			continue
		case scanner.EOF:
			return "", "", nil, false

	p.loadDefines(f)
	p.typedefs = map[string]bool{}
	p.typedefList = nil
	numTypedefs := -1
	for len(p.typedefs) > numTypedefs {
		numTypedefs = len(p.typedefs)
		// Also ask about any typedefs we've seen so far.
		for _, info := range p.typedefList {
			if f.Name[info.typedef] != nil {
				continue
			}
			n := &Name{
				Go: info.typedef,
				C:  info.typedef,
			}
			f.Name[info.typedef] = n

	}

	context := w.context
	if context == nil {
		context = &build.Default
	}

	// Look in cache.
	// If we've already done an import with the same set
	// of relevant tags, reuse the result.
	var key string
	if usePkgCache {
		if tags, ok := pkgTags[dir]; ok {
			key = tagKey(dir, context, tags)

	for {
		header, err := tr.Next()
		if err == io.EOF {
			break
		}
		if err != nil {
			t.Fatalf("Failed to read header: %s", err)
		}
		if header.Typeflag != TypeReg {
			t.Fatalf("Typeflag should've been %d, found %d", TypeReg, header.Typeflag)
		}
	}
}

// failOnceWriter fails exactly once and then always reports success.
type failOnceWriter bool

func (w *failOnceWriter) Write(b []byte) (int, error) {