// Copyright 2009 The Go Authors. All rights reserved.

// Use of this source code is governed by a BSD-style

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

// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris

// Package unix contains an interface to the low-level operating system

// primitives. OS details vary depending on the underlying system, and

// by default, godoc will display OS-specific documentation for the current

// system. If you want godoc to display OS documentation for another

// system, set $GOOS and $GOARCH to the desired system. For example, if

// you want to view documentation for freebsd/arm on linux/amd64, set $GOOS

// to freebsd and $GOARCH to arm.

//

// The primary use of this package is inside other packages that provide a more

// portable interface to the system, such as "os", "time" and "net".  Use

// those packages rather than this one if you can.

//

// For details of the functions and data types in this package consult

// the manuals for the appropriate operating system.

//

// These calls return err == nil to indicate success; otherwise

// err represents an operating system error describing the failure and

// holds a value of type syscall.Errno.

package unix // import "golang.org/x/sys/unix"

import "strings"

// ByteSliceFromString returns a NUL-terminated slice of bytes

// containing the text of s. If s contains a NUL byte at any

// location, it returns (nil, EINVAL).

func ByteSliceFromString(s string) ([]byte, error) {

	if strings.IndexByte(s, 0) != -1 {

		return nil, EINVAL

	}

	a := make([]byte, len(s)+1)

	copy(a, s)

	return a, nil

}

// BytePtrFromString returns a pointer to a NUL-terminated array of

// bytes containing the text of s. If s contains a NUL byte at any

// location, it returns (nil, EINVAL).

func BytePtrFromString(s string) (*byte, error) {

	a, err := ByteSliceFromString(s)

	if err != nil {

		return nil, err

	}

	return &a[0], nil

}

// Single-word zero for use when we need a valid pointer to 0 bytes.

var _zero uintptr