return nil, err
	}

	oldState := State{state{termios: *termios}}

	// This attempts to replicate the behaviour documented for cfmakeraw in
	// the termios(3) manpage.
	termios.Iflag &^= unix.IGNBRK | unix.BRKINT | unix.PARMRK | unix.ISTRIP | unix.INLCR | unix.IGNCR | unix.ICRNL | unix.IXON
	termios.Oflag &^= unix.OPOST
	termios.Lflag &^= unix.ECHO | unix.ECHONL | unix.ICANON | unix.ISIG | unix.IEXTEN

		$2 ~ /^I(SIG|CANON|CRNL|EXTEN|MAXBEL|STRIP|UTF8)$/ ||
		$2 ~ /^IGN/ ||
		$2 ~ /^IX(ON|ANY|OFF)$/ ||
		$2 ~ /^IN(LCR|PCK)$/ ||
		$2 ~ /(^FLU?SH)|(FLU?SH$)/ ||
		$2 ~ /^C(LOCAL|READ)$/ ||
		$2 == "BRKINT" ||
		$2 == "HUPCL" ||
		$2 == "PENDIN" ||
		$2 == "TOSTOP" ||
		$2 ~ /^PAR/ ||
		$2 ~ /^SIG[^_]/ ||
		$2 ~ /^O[CNPFP][A-Z]+[^_][A-Z]+$/ ||
		$2 ~ /^IN_/ ||
		$2 ~ /^LOCK_(SH|EX|NB|UN)$/ ||

	VSWTC    = 0x7
	VSTART   = 0x8
	VSTOP    = 0x9
	VSUSP    = 0xa
	VEOL     = 0xb
	VREPRINT = 0xc
	VDISCARD = 0xd
	VWERASE  = 0xe
	VLNEXT   = 0xf
	VEOL2    = 0x10
	IGNBRK   = 0x1
	BRKINT   = 0x2
	IGNPAR   = 0x4
	PARMRK   = 0x8
	INPCK    = 0x10
	ISTRIP   = 0x20
	INLCR    = 0x40
	IGNCR    = 0x80
	ICRNL    = 0x100
	IUCLC    = 0x200
	IXON     = 0x400
	IXANY    = 0x800

	VSWTC    = 0x7
	VSTART   = 0x8
	VSTOP    = 0x9
	VSUSP    = 0xa
	VEOL     = 0xb
	VREPRINT = 0xc
	VDISCARD = 0xd
	VWERASE  = 0xe
	VLNEXT   = 0xf
	VEOL2    = 0x10
	IGNBRK   = 0x1
	BRKINT   = 0x2
	IGNPAR   = 0x4
	PARMRK   = 0x8
	INPCK    = 0x10
	ISTRIP   = 0x20
	INLCR    = 0x40
	IGNCR    = 0x80
	ICRNL    = 0x100
	IUCLC    = 0x200
	IXON     = 0x400
	IXANY    = 0x800

	VSWTC    = 0x7
	VSTART   = 0x8
	VSTOP    = 0x9
	VSUSP    = 0xa
	VEOL     = 0xb
	VREPRINT = 0xc
	VDISCARD = 0xd
	VWERASE  = 0xe
	VLNEXT   = 0xf
	VEOL2    = 0x10
	IGNBRK   = 0x1
	BRKINT   = 0x2
	IGNPAR   = 0x4
	PARMRK   = 0x8
	INPCK    = 0x10
	ISTRIP   = 0x20
	INLCR    = 0x40
	IGNCR    = 0x80
	ICRNL    = 0x100
	IUCLC    = 0x200
	IXON     = 0x400
	IXANY    = 0x800

		$2 ~ /^I(SIG|CANON|CRNL|EXTEN|MAXBEL|STRIP|UTF8)$/ ||
		$2 ~ /^IGN/ ||
		$2 ~ /^IX(ON|ANY|OFF)$/ ||
		$2 ~ /^IN(LCR|PCK)$/ ||
		$2 ~ /(^FLU?SH)|(FLU?SH$)/ ||
		$2 ~ /^C(LOCAL|READ)$/ ||
		$2 == "BRKINT" ||
		$2 == "HUPCL" ||
		$2 == "PENDIN" ||
		$2 == "TOSTOP" ||
		$2 ~ /^PAR/ ||
		$2 ~ /^SIG[^_]/ ||
		$2 ~ /^O[CNPFP][A-Z]+[^_][A-Z]+$/ ||
		$2 ~ /^IN_/ ||
		$2 ~ /^LOCK_(SH|EX|NB|UN)$/ ||

		$2 ~ /^IGN/ ||
		$2 ~ /^IX(ON|ANY|OFF)$/ ||
		$2 ~ /^IN(LCR|PCK)$/ ||
		$2 !~ "X86_CR3_PCID_NOFLUSH" &&
		$2 ~ /(^FLU?SH)|(FLU?SH$)/ ||
		$2 ~ /^C(LOCAL|READ|MSPAR|RTSCTS)$/ ||
		$2 == "BRKINT" ||
		$2 == "HUPCL" ||
		$2 == "PENDIN" ||
		$2 == "TOSTOP" ||
		$2 == "XCASE" ||
		$2 == "ALTWERASE" ||
		$2 == "NOKERNINFO" ||
		$2 == "NFDBITS" ||
		$2 ~ /^PAR/ ||
		$2 ~ /^SIG[^_]/ ||

// license that can be found in the LICENSE file.

//go:build zos && s390x

// Hand edited based on zerrors_linux_s390x.go
// TODO: auto-generate.

package unix

const (
	BRKINT                   = 0x0001
	CLOCAL                   = 0x1
	CLOCK_MONOTONIC          = 0x1
	CLOCK_PROCESS_CPUTIME_ID = 0x2
	CLOCK_REALTIME           = 0x0
	CLOCK_THREAD_CPUTIME_ID  = 0x3

	BPF_SUB                           = 0x10
	BPF_TAX                           = 0x0
	BPF_TXA                           = 0x80
	BPF_W                             = 0x0
	BPF_X                             = 0x8
	BRKINT                            = 0x2
	CFLUSH                            = 0xf
	CLOCAL                            = 0x8000
	CREAD                             = 0x800
	CS5                               = 0x0

	B38400                        = 0xf
	B4800                         = 0xc
	B50                           = 0x1
	B600                          = 0x8
	B75                           = 0x2
	B9600                         = 0xd
	BRKINT                        = 0x2
	CFLUSH                        = 0xf
	CLOCAL                        = 0x800
	CREAD                         = 0x80
	CS5                           = 0x0
	CS6                           = 0x10