iostream.cpp

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    char fill_char = stream.fill();
    if (padding > 0
	&& pad_kind != (ios::fmtflags)ios::left
	&& pad_kind != (ios::fmtflags)ios::internal) // Default (right) adjust.
	if (_IO_padn(sbuf, fill_char, padding) < padding)
	  goto failed;
    if (sign < 0 || show_pos)
      {
	char ch = sign < 0 ? '-' : '+';
	if (sbuf->sputc(ch) < 0)
	  goto failed;
      }
    if (show_base_len)
	if (_IO_sputn(sbuf, show_base, show_base_len) <= 0)
	  goto failed;
    if (pad_kind == (ios::fmtflags)ios::internal && padding > 0)
      if (_IO_padn(sbuf, fill_char, padding) < padding)
	goto failed;
    if (_IO_sputn (sbuf, buf_ptr, buf_len) != buf_len)
      goto failed;
    if (pad_kind == (ios::fmtflags)ios::left && padding > 0) // Left adjustment
      if (_IO_padn(sbuf, fill_char, padding) < padding)
	goto failed;
    stream.osfx();
    return;
  failed:
    stream.set(ios::badbit);
    stream.osfx();
}

ostream& ostream::operator<<(int n)
{
    if (opfx()) {
	_IO_cleanup_region_start ((void (*) __P ((void *))) _IO_funlockfile,
				  _strbuf);
	int sign = 1;
	unsigned int abs_n = (unsigned)n;
	if (n < 0 && (flags() & (ios::oct|ios::hex)) == 0)
	    abs_n = -((unsigned)n), sign = -1;
	write_int(*this, abs_n, sign);
	_IO_cleanup_region_end (0);
    }
    return *this;
}

ostream& ostream::operator<<(unsigned int n)
{
    if (opfx()) {
	_IO_cleanup_region_start ((void (*) __P ((void *))) _IO_funlockfile,
				  _strbuf);
	write_int(*this, n, 0);
	_IO_cleanup_region_end (0);
    }
    return *this;
}


ostream& ostream::operator<<(long n)
{
    if (opfx()) {
	_IO_cleanup_region_start ((void (*) __P ((void *))) _IO_funlockfile,
				  _strbuf);
	int sign = 1;
	unsigned long abs_n = (unsigned long)n;
	if (n < 0 && (flags() & (ios::oct|ios::hex)) == 0)
	    abs_n = -((unsigned long)n), sign = -1;
	write_int(*this, abs_n, sign);
	_IO_cleanup_region_end (0);
    }
    return *this;
}

ostream& ostream::operator<<(unsigned long n)
{
    if (opfx()) {
	_IO_cleanup_region_start ((void (*) __P ((void *))) _IO_funlockfile,
				  _strbuf);
	write_int(*this, n, 0);
	_IO_cleanup_region_end (0);
    }
    return *this;
}

#if defined(__GNUC__) && !defined(__STRICT_ANSI__)
ostream& ostream::operator<<(long long n)
{
    if (opfx()) {
	_IO_cleanup_region_start ((void (*) __P ((void *))) _IO_funlockfile,
				  _strbuf);
	int sign = 1;
	unsigned long long abs_n = (unsigned long long)n;
	if (n < 0 && (flags() & (ios::oct|ios::hex)) == 0)
	    abs_n = -((unsigned long long)n), sign = -1;
	write_int(*this, abs_n, sign);
	_IO_cleanup_region_end (0);
    }
    return *this;
}


ostream& ostream::operator<<(unsigned long long n)
{
    if (opfx()) {
	_IO_cleanup_region_start ((void (*) __P ((void *))) _IO_funlockfile,
				  _strbuf);
	write_int(*this, n, 0);
	_IO_cleanup_region_end (0);
    }
    return *this;
}
#endif /*__GNUC__*/

ostream& ostream::operator<<(double n)
{
    if (opfx()) {
	_IO_cleanup_region_start ((void (*) __P ((void *))) _IO_funlockfile,
				  _strbuf);
	// Uses __cvt_double (renamed from static cvt), in Chris Torek's
	// stdio implementation.  The setup code uses the same logic
	// as in __vsbprintf.C (also based on Torek's code).
	int format_char;
	if ((flags() & ios::floatfield) == ios::fixed)
	    format_char = 'f';
	else if ((flags() & ios::floatfield) == ios::scientific)
	    format_char = flags() & ios::uppercase ? 'E' : 'e';
	else
	    format_char = flags() & ios::uppercase ? 'G' : 'g';

	int prec = precision();
	if (prec <= 0 && !(flags() & ios::fixed))
	  prec = 6; /* default */

	// Do actual conversion.
#if _G_HAVE_PRINTF_FP
	{
	  struct printf_info info = { prec: prec,
				      width: width(0),
				      spec: format_char,
				      is_long_double: 0,
				      is_short: 0,
				      is_long: 0,
				      alt: (flags() & ios::showpoint) != 0,
				      space: 0,
				      left: (flags() & ios::left) != 0,
				      showsign: (flags() & ios::showpos) != 0,
				      group: 0,
				      pad: fill()
#if defined __GLIBC__ && __GLIBC__ >= 2
				      , extra: 0
#endif
	  };
	  const void *ptr = (const void *) &n;
	  if (__printf_fp (rdbuf(), &info, &ptr) < 0)
	    set(ios::badbit|ios::failbit);
	}
#elif defined  _IO_USE_DTOA
	if (_IO_outfloat(n, rdbuf(), format_char, width(0),
			 prec, flags(),
			 flags() & ios::showpos ? '+' : 0,
			 fill()) < 0)
	    set(ios::badbit|ios::failbit); // ??
#else
	int fpprec = 0; // 'Extra' (suppressed) floating precision.
	if (prec > MAXFRACT) {
	    if (flags() & (ios::fixed|ios::scientific) & ios::showpos)
		fpprec = prec - MAXFRACT;
	    prec = MAXFRACT;
	}
	int negative;
	char buf[BUF];
	int sign = '\0';
	char *cp = buf;
	*cp = 0;
	int size = __cvt_double(n, prec,
				flags() & ios::showpoint ? 0x80 : 0,
				&negative,
				format_char, cp, buf + sizeof(buf));
	if (negative) sign = '-';
	else if (flags() & ios::showpos) sign = '+';
	if (*cp == 0)
	    cp++;

	// Calculate padding.
	int fieldsize = size + fpprec;
	if (sign) fieldsize++;
	int padding = 0;
	int w = width(0);
	if (fieldsize < w)
	    padding = w - fieldsize;

	// Do actual output.
	register streambuf* sbuf = rdbuf();
	register i;
	char fill_char = fill();
	ios::fmtflags pad_kind =
	    flags() & (ios::left|ios::right|ios::internal);
	if (pad_kind != (ios::fmtflags)ios::left // Default (right) adjust.
	    && pad_kind != (ios::fmtflags)ios::internal)
	    for (i = padding; --i >= 0; ) sbuf->sputc(fill_char);
	if (sign)
	    sbuf->sputc(sign);
	if (pad_kind == (ios::fmtflags)ios::internal)
	    for (i = padding; --i >= 0; ) sbuf->sputc(fill_char);

	// Emit the actual concented field, followed by extra zeros.
	_IO_sputn (sbuf, cp, size);
	for (i = fpprec; --i >= 0; ) sbuf->sputc('0');

	if (pad_kind == (ios::fmtflags)ios::left) // Left adjustment
	    for (i = padding; --i >= 0; ) sbuf->sputc(fill_char);
#endif
	osfx();
	_IO_cleanup_region_end (0);
    }
    return *this;
}

/* Begin VxWorks specific */
#ifndef _NO_LONG_DOUBLE_
#if _G_HAVE_LONG_DOUBLE_IO
ostream& ostream::operator<<(long double n)
{
  if (opfx())
    {
      _IO_cleanup_region_start ((void (*) __P ((void *))) _IO_funlockfile,
				_strbuf);
      int format_char;
      if ((flags() & ios::floatfield) == ios::fixed)
	format_char = 'f';
      else if ((flags() & ios::floatfield) == ios::scientific)
	format_char = flags() & ios::uppercase ? 'E' : 'e';
      else
	format_char = flags() & ios::uppercase ? 'G' : 'g';

      int prec = precision();
      if (prec <= 0 && !(flags() & ios::fixed))
	prec = 6; /* default */

#if _G_HAVE_PRINTF_FP
      // Do actual conversion.
      struct printf_info info = { prec: prec,
				  width: width(0),
				  spec: format_char,
				  is_long_double: 1,
				  is_short: 0,
				  is_long: 0,
				  alt: (flags() & ios::showpoint) != 0,
				  space: 0,
				  left: (flags() & ios::left) != 0,
				  showsign: (flags() & ios::showpos) != 0,
				  group: 0,
				  pad: fill()
#if defined __GLIBC__ && __GLIBC__ >= 2
				  , extra: 0
#endif
      };

      const void *ptr = (const void *) &n;

      if (__printf_fp (rdbuf(), &info, &ptr) < 0)
	set (ios::badbit|ios::failbit);
#else
# error "long double I/O using dtoa or cvt_double is not implemented"
#endif
      osfx();
      _IO_cleanup_region_end (0);
    }
  return *this;
}
#endif
#endif
/* End VxWorks specific */

ostream& ostream::operator<<(const char *s)
{
  if (opfx())
    {
      _IO_cleanup_region_start ((void (*) __P ((void *))) _IO_funlockfile,
				_strbuf);
      if (s == NULL)
	s = "(null)";
      int len = strlen(s);
      int w = width(0);
// FIXME: Should we: if (w && len>w) len = w;
      char fill_char = fill();
      register streambuf *sbuf = rdbuf();
      register int padding = w > len ? w - len : 0;
      if (!(flags() & ios::left) && padding > 0) // Default adjustment.
	if (_IO_padn(sbuf, fill_char, padding) != padding)
	  {
	    set(ios::badbit);
	    goto failed;
	  }
      if (_IO_sputn (sbuf, s, len) != len)
	{
	  set(ios::badbit);
	  goto failed;
	}
      if (flags() & ios::left && padding > 0) // Left adjustment.
	if (_IO_padn(sbuf, fill_char, padding) != padding)
	  set(ios::badbit);
      osfx();
     failed:
      _IO_cleanup_region_end (0);
    }
  return *this;
}

#if 0
ostream& ostream::operator<<(const void *p)
{ Is in osform.cc, to avoid pulling in all of _IO_vfprintf by this file. */ }
#endif

ostream& ostream::operator<<(register streambuf* sbuf)
{
  if (opfx())
    {
      _IO_cleanup_region_start ((void (*) __P ((void *))) _IO_funlockfile,
				_strbuf);
      char buffer[_IO_BUFSIZ];
      register streambuf* outbuf = _strbuf;
      for (;;)
	{
	  _IO_size_t count = _IO_sgetn(sbuf, buffer, _IO_BUFSIZ);
	  if (count <= 0)
	    break;
	  if (_IO_sputn(outbuf, buffer, count) != count)
	    {
	      set(ios::badbit);
	      break;
	    }
	}
      osfx();
      _IO_cleanup_region_end (0);
    }
  return *this;
}

ostream::ostream(streambuf* sb, ostream* tied)
{
  init (sb, tied);
}

ostream& ostream::seekp(streampos pos)
{
    pos = _strbuf->pubseekpos(pos, ios::out);
    if (pos == streampos(EOF))
	set(ios::badbit);
    return *this;
}

ostream& ostream::seekp(streamoff off, _seek_dir dir)
{
  streampos pos = _IO_seekoff (_strbuf, off, (int) dir, _IOS_OUTPUT);
  if (pos == streampos(EOF))
    set(ios::badbit);
  return *this;
}

streampos ostream::tellp()
{
#if 1
    streampos pos = _IO_seekoff (_strbuf, 0, _IO_seek_cur, _IOS_OUTPUT);
#else
    streampos pos = _strbuf->pubseekoff(0, ios::cur, ios::out);
#endif
    if (pos == streampos(EOF))
	set(ios::badbit);
    return pos;
}

ostream& ostream::flush()
{
    if (_strbuf->sync())
	set(ios::badbit);
    return *this;
}

ostream& flush(ostream& outs)
{
  return outs.flush();
}

istream& ws(istream& ins)
{
    if (ins.ipfx1()) {
	_IO_cleanup_region_start ((void (*) __P ((void *))) _IO_funlockfile,
				  ins._strbuf);
	int ch = skip_ws(ins._strbuf);
	if (ch == EOF)
	    ins.set(ios::eofbit);
	else
	    ins._strbuf->sputbackc(ch);
	ins.isfx();
	_IO_cleanup_region_end (0);
    }
    return ins;
}

// Skip white-space.  Return 0 on failure (EOF), or 1 on success.
// Differs from ws() manipulator in that failbit is set on EOF.
// Called by ipfx() and ipfx0() if needed.

int istream::_skip_ws()
{
    int ch = skip_ws(_strbuf);
    if (ch == EOF) {
	set(ios::eofbit|ios::failbit);
	return 0;
    }
    else {
	_strbuf->sputbackc(ch);
	return 1;
    }
}

ostream& ends(ostream& outs)
{
    outs.put('\0');
    return outs;
}

ostream& endl(ostream& outs)
{
    return flush(outs.put('\n'));
}

istream& lock(istream& ins)
{
  _IO_flockfile (ins._strbuf);
  return ins;
}
istream& unlock(istream& ins)
{
  _IO_funlockfile (ins._strbuf);
  return ins;
}
ostream& lock(ostream& outs)
{
  _IO_flockfile (outs._strbuf);
  return outs;
}
ostream& unlock(ostream& outs)
{
  _IO_funlockfile (outs._strbuf);
  return outs;
}


ostream& ostream::write(const char *s, streamsize n)
{
    if (opfx()) {
	_IO_cleanup_region_start ((void (*) __P ((void *))) _IO_funlockfile,
				  _strbuf);
	if (_IO_sputn(_strbuf, s, n) != n)
	    set(ios::failbit);
	osfx();
	_IO_cleanup_region_end (0);
    }
    return *this;
}

void ostream::do_osfx()
{
    if (flags() & ios::unitbuf)
	flush();
    if (flags() & ios::stdio) {
	fflush(stdout);
	fflush(stderr);
    }
}

iostream::iostream(streambuf* sb, ostream* tied)
{
  init (sb, tied);
}

// NOTE: extension for compatibility with old libg++.
// Not really compatible with fistream::close().
#ifdef _STREAM_COMPAT
void ios::close()
{
  if (_strbuf->_flags & _IO_IS_FILEBUF)
    ((struct filebuf*)rdbuf())->close();
  else if (_strbuf != NULL)
    rdbuf()->sync();
  _strbuf = NULL;
  _state = badbit;
}

int istream::skip(int i)
{
    int old = (_flags & ios::skipws) != 0;
    if (i)
	_flags |= ios::skipws;
    else
	_flags &= ~ios::skipws;
    return old;
}
#endif