O_TRUNC   = 16
	O_CLOEXEC = 32
	O_EXCL    = 0x1000
)

// Bind flags
const (
	MORDER  = 0x0003 // mask for bits defining order of mounting
	MREPL   = 0x0000 // mount replaces object
	MBEFORE = 0x0001 // mount goes before others in union directory
	MAFTER  = 0x0002 // mount goes after others in union directory
	MCREATE = 0x0004 // permit creation in mounted directory
	MCACHE  = 0x0010 // cache some data
	MMASK   = 0x0017 // all bits on

				`0x0000 00000\s\(.*\)\tBC\t\$12,\sCR0EQ,\s8`,
				`0x0004 00004\s\(.*\)\tJMP\t131128`}},
		// bdnz (BC 16,0,tgt) <-> bdz (BC 18,0,+4) conversion (insert one jump)
		{"BC 16,0,",
			[]string{``,
				`0x20030 131120\s\(.*\)\tBC\t\$18,\sCR0LT,\s131128`,
				`0x20034 131124\s\(.*\)\tJMP\t0`},
			[]string{``,
				`0x0000 00000\s\(.*\)\tBC\t\$18,\sCR0LT,\s8`,
				`0x0004 00004\s\(.*\)\tJMP\t131128`}},
		{"BC 18,0,",
			[]string{``,

	IMAGE_REL_ARM_BRANCH11           = 0x0004
	IMAGE_REL_ARM_SECTION            = 0x000E
	IMAGE_REL_ARM_SECREL             = 0x000F
	IMAGE_REL_ARM_MOV32              = 0x0010
	IMAGE_REL_THUMB_MOV32            = 0x0011
	IMAGE_REL_THUMB_BRANCH20         = 0x0012
	IMAGE_REL_THUMB_BRANCH24         = 0x0014
	IMAGE_REL_THUMB_BLX23            = 0x0015
	IMAGE_REL_ARM_PAIR               = 0x0016
	IMAGE_REL_ARM64_ABSOLUTE         = 0x0000

    }
  }

  // 128 - [chars 0x0000 to 0x007f]
  private static final long ONE_BYTE_ROUNDTRIPPABLE_CHARACTERS = 0x007f - 0x0000 + 1;

  // 128
  private static final long EXPECTED_ONE_BYTE_ROUNDTRIPPABLE_COUNT =
      ONE_BYTE_ROUNDTRIPPABLE_CHARACTERS;

  // 1920 [chars 0x0080 to 0x07FF]
  private static final long TWO_BYTE_ROUNDTRIPPABLE_CHARACTERS = 0x07FF - 0x0080 + 1;

  // 18,304

	DNS_TYPE_SOA     = 0x0006
	DNS_TYPE_MB      = 0x0007
	DNS_TYPE_MG      = 0x0008
	DNS_TYPE_MR      = 0x0009
	DNS_TYPE_NULL    = 0x000a
	DNS_TYPE_WKS     = 0x000b
	DNS_TYPE_PTR     = 0x000c
	DNS_TYPE_HINFO   = 0x000d
	DNS_TYPE_MINFO   = 0x000e
	DNS_TYPE_MX      = 0x000f
	DNS_TYPE_TEXT    = 0x0010
	DNS_TYPE_RP      = 0x0011
	DNS_TYPE_AFSDB   = 0x0012
	DNS_TYPE_X25     = 0x0013
	DNS_TYPE_ISDN    = 0x0014

	// 0x80, Cr: 0x80} and c1 := Gray{Y: y} then c0.RGBA() should equal
	// c1.RGBA(). Specifically, if y == 0 then "R = etc >> 8" should yield
	// 0x0000 and if y == 0xff then "R = etc >> 8" should yield 0xffff. If we
	// used a constant rounding adjustment of 1<<15, then it would yield 0x0080
	// and 0xff80 respectively.
	//
	// Note that when cb == 0x80 and cr == 0x80 then the formulae collapse to:
	//	R = YY1 >> n
	//	G = YY1 >> n

		// The following code simulates an additional check for x == xx and
		// handling the ASCII and invalid cases accordingly. This mask-and-or
		// approach prevents an additional branch.
		mask := rune(x) << 31 >> 31 // Create 0x0000 or 0xFFFF.
		return rune(p[0])&^mask | RuneError&mask, 1
	}
	sz := int(x & 7)
	accept := acceptRanges[x>>4]
	if n < sz {
		return RuneError, 1
	}
	b1 := p[1]
	if b1 < accept.lo || accept.hi < b1 {

const (
	DNS_TYPE_A       = 0x0001
	DNS_TYPE_NS      = 0x0002
	DNS_TYPE_MD      = 0x0003
	DNS_TYPE_MF      = 0x0004
	DNS_TYPE_CNAME   = 0x0005
	DNS_TYPE_SOA     = 0x0006
	DNS_TYPE_MB      = 0x0007
	DNS_TYPE_MG      = 0x0008
	DNS_TYPE_MR      = 0x0009
	DNS_TYPE_NULL    = 0x000a
	DNS_TYPE_WKS     = 0x000b
	DNS_TYPE_PTR     = 0x000c
	DNS_TYPE_HINFO   = 0x000d
	DNS_TYPE_MINFO   = 0x000e

	0xd2: 0x000b, 0xd3: 0x000b, 0xd4: 0x000b, 0xd5: 0x000b, 0xd6: 0x000b, 0xd7: 0x000b,
	0xd8: 0x000b, 0xd9: 0x000b, 0xda: 0x000b, 0xdb: 0x000b, 0xdc: 0x000b, 0xdd: 0x000b,
	0xde: 0x000b, 0xdf: 0x000b, 0xe0: 0x0006, 0xe1: 0x000a, 0xe2: 0x0004, 0xe3: 0x0004,
	0xe4: 0x0004, 0xe5: 0x0004, 0xe6: 0x000a, 0xe7: 0x000a, 0xe8: 0x000a, 0xe9: 0x000a,
	0xeb: 0x000a, 0xec: 0x000a, 0xed: 0x000b, 0xee: 0x000a, 0xef: 0x000a,

		opaqueGray       = color.NRGBA{0x99, 0x99, 0x99, 0xff}
		transparentBlue  = color.NRGBA{0x00, 0x00, 0xff, 0x00}
		transparentGreen = color.NRGBA{0x00, 0xff, 0x00, 0x00}
		transparentRed   = color.NRGBA{0xff, 0x00, 0x00, 0x00}

		opaqueGray64        = color.NRGBA64{0x9999, 0x9999, 0x9999, 0xffff}
		transparentPurple64 = color.NRGBA64{0xfedc, 0x0000, 0x7654, 0x0000}
	)

	// dst and src are 1x3 images but the dr rectangle (and hence the overlap)